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309 Cards in this Set
- Front
- Back
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Endo means
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within
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crine means
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secretion
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Endocrine
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secretion of hormones WITHIN the body to act internally
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Exocrine
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secretion of substance to EXTERIOR or ogans that open to exterior such as SWEAT gland SALVIA glands mucus, and gastric enzymes
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The endocrine system serves to
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maintain homeostatis of many physologic function
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What are mechanisms are central to endorcinre function
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cell to cell communication by chemicals
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Endocrine--what are major functions of hormoes
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PIG ROW
Production of metabolic energy Immune system (inflammtion, response to stress) Growth and development Reproductive functions Ohter--erythropoiten Water adn electrolyte metabolism |
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Is there overlap of hormonal activites to closely regulate physiolgic function and mataintain homeostatis
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YES
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What are functional classficiation of hormones
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SAD PT
Synergistic hormones Antagonistic hormones Direct effect Permissive effect Tropic hormones |
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What is a synergistic hormone and example
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Syn--two or mroe hormones with similar effect on a target tissues but together a greater effect (thyroid and epi)
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What are antagoinstic hormones and example
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hormones with opposing effects (insulin and glucagon)
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WHat is direct effect hormone
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action of hormone on a target cell
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What is a permisisve effect hormone example
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hormone with NO obvious effect on a target cell, but its presence allows greater effect of another hormone (cortisol and epi)
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What is a tropic hormone, example
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hormone taht stimulates a 2nd endocrine hormone to secrete a hormone (TSH act on Tyroid gland)
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Tropic hormones also have a long-term effect on
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the growth and maintenance of target endocrine tissue
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What are 2 principal systems for most communication between cells
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Nervous system and endocrine system
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What are autocrine cells
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secrete substance to at on themselves
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What are paracrine cells
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secrete substance to act on acjacent nearby cells by diffusion
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DISTANT cell to cell communication occur by hormones
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secreted into blood
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Typically an endocrien cell receives information in the form of
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a chemical message from the blood stream, then they secrete their own specfic hormonal singal to the blood that is communicated to target cell
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Endocrine cells then secrete
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their own speicifal hormonal singal into the blood that is communicated to the target cell
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Neuroendocrine function as criucal link between
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the nerous and endorcine system
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What stimulates the Nueroendocrine cell
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a neuron
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Unlike a neuron the NE secretes
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a hormone direcetly into blood that goes to target cell
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Do Neuroednocrine cells convert an electrochemical singal into a hormonal singal in the blood stream
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YES
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2 pathways Specialized hypothalamic neurons either
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1. hormones that act on cells in anterior pitutiary to secrete hormones or
2. terminate in posterior pituitary adn secrete substanes directly into bloodstem |
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THe ANS controls hormone secretion
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form the adrenal medulla
2. ro inneravtes an endocrine gland to activate or inhibit the cell from producing and secreting a hormone |
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What are neuroendocrine organs
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hypothalamus and adrenal medulla
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What makes hypothalamus and adrenal medulla a neuroendocrine organ
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neural tissues that produce and secrete hormones directly into the bloodsteam
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Endocrine glands are stimulated to manufacture an drelease their hormones by 3 major types of stimuli
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1. Humoral
2. Neural 3. Hormonal |
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What is humoral stimuli
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endocrine glands that secrte theri hormones in direct response to chaning blood levels
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What is an example of humoral stimulate
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the endocrine galnd parathroid gland secrte PTH
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What is hormonal stimuli
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endocrine glands that secrete their hormones in reponse to hormones produced by other endocrine organs
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What is neural stimuli
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nerve fibers that stimuate hormone releases
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Endocrine glands have capacity to
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produce hormones, secrete hormones, monitor hormone levels and regulate hormone synthesis and secretion
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How do endocrine glands regulate hormone synthesis and secretion
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through feedback mechansisms
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Negative feeback mechanism are MOST common what do they do
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stabilsize, balance and take back to normal
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What do positive feedback mechanisms do
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INCREASE function--destablizes
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What is an example of a simple negative feedback loop
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Beta isel cells in pancrease repond to High Blood glucose by producing and secreting insulin into blood steam, insulin lowers Blod glucose, which reducues pancreatic simulation, which lowers insulin secretion
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Does negative coplex feedback loop have 3 layers or regulation--
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YES
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3 chemical caterogries of hormones
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amino acid derivates
peptides or proteins steriods |
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Tyrosine forms what hormone
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epienehrine and thyroid hormone
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Typrophan forms what hormone
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melatonin
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THe size range of peptide or protein hormones ranges from
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small to medium to large
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What is small peptide
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TRH (tyrotropin releasing hormone)
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WHat is a medium peptide
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ACTH adrenocorticotropic hormone or PTH (parathyroid hormone)
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What is large peptide
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GH growth hormone
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The five principal categories of steriod-bases hormones are all dervived from
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chloesterol
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What are main steriod hormones
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estrogens, progestins, tesosterone, mineralcorticoids, and glucoorticouds
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What are example of glycoproteins
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FSH, LH and TSH (thyroid stimulating hormone
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Is solubility of hormones in the bloodstream critical to their transport to target organs
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YES
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What are water-soluble hormones
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peptide adn protein hormones, and a.a. derivatives (most)
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What are lipid soluble hormones
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steriods and thyroid hormone
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How do hormones overcome solublility problems in blood stream
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bound to large "carrier or transport proteins
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Two catergoires of transport proteins
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specific transport proteins and general transport proteins
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What are specifc transport protiens
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Cortisol, Thyroxine and Sex steriod binding globulins
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Cortisol binding globulin , what hormones does it princially transport
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cortisol and some aldosterone
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What does Tyroxine binding globulin specially transport
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throxine (T4)
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What does Sex steriod binding globulin speically transport
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testosterone and estradiol
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What are general transport proteins
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albumin and transthyretin (prealbumin)
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What does albumin mainly transport
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steriods and thyroxine
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What does transthyretin transport
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Some steriods and throxine
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The free and bound forms of horome exist in blood plasma as
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a dynamic equilibirum with one another
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Mostly equilbrium favors
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the bound hormones ( but a same amoutn is also present in free state
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What is the physiological acitve form of hormones
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FREE HORMONE
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Why is free hormones the physiologically active form
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only free hormone moves from blood to reach cells and interacts with receptors
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Due to reservior and buffer system, what happens if there is a sudden large burst of hormone secretion
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most of it would be bound to carrier protein, and free hormone level will increase only slightly
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What serve as the reservior and buffer systmems
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carrier proteins--help maintain a constnat level of FREE hormone in blood
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What type of hormone is subject to metabolism and excretion
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ONLY FREE HORMONE
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DO protein bound hormones tend to reamin in plasma for longer period of time
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YES
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MOSTLY, is the hormones secreted by an endocrine cell the form directly responsibile for producing the biological effect
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YES
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What type of hormones can be excreted directly though kidneys into urine without being metabolized and inactivated
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water-soluble
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Nearly all hormones are inactived by
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enzymatic metabolism and excrted via kidney or liver
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Where does water solbule hormones bind and action
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to CELL surface and trigger 2nd messeneger response--leads to biological response
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What is receptor up-regulation
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increases the number of receptors and is assoiced with chronic low levels of hormones interacting with receptors
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What is receptor down regulation
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assoicated with excress amounts of hormones leads to endocytosis of receptor from the plasma membrane surface
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Where do lipid soluble hormones binds (steriods and thyroid)
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to intracellualr receptors and trigger gene expression leading to synthesis of specific proteins that change cell function
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Which is fastest water soluble or lipid soluble
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WATER-souble
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Once a water soluble hormone is withdrawn, when does cell function return to basal state
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rapidly returns to basal state
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After removal of a lipid soluble hormone, when does cell return to normal
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much slower than water soluble
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With water and lipid soluble hormones, it can regulate many cellular process on both a acute and chonric basis
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YES
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What are hormones taht are water soluble and act though AC and cAMP system
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LEAP TAG F
LH Epinehrine ACTH PTH TSH ADH Glucagon FSH |
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Target tissue of ACTH
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adrenal cortex
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What is target tissue of EPI Norepiephrine
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heart, smooth muscle and adipose
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What is target tissue of glucagon
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liver
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What is target tissue of FSH and LH
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testes and ovaries
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What is target tissue of PTH
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kidney and bone
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What is target of ADH
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kidney
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What are the 4 types of receptors
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Receptors link to AC/CAMP
Linked to IP3 and DAG Link to ion channels Linked to PRotein tyrosine kinase activity |
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What are example of a receptor linked to ion channel
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noepheinerphine
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What is an example of receptor linked to protein/tyrosine kinase acitivity
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insulin
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What is an example of Gene expression mehansims
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aldosterone
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What is an exmaple of a recepor linked to IP3 and DAG
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Oxytocin and ADH
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Where is pitutiary gland located
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just below hypothalamus
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The pituatry gland consists of 3 lobes:
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Anterior intermediate and posterior lobe (intermediate no fucntion in humans)
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How is pituary connect to hypothalamus
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thin tissue--the pititary stalk
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What are embryonic orgins of anterior pituitary
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orgainates from oral cavity (non-neural tissue)
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What are embroyonic orgins of posterior pituitary
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orginates from hypothalamus (neural tissue orgins) migrates downward
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What part of pitutiary has neural orgins--so a NEURAL connection with hypothalamus
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POSTERIOR pituitary
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Neurons orgainate in 2 distinct areas of the hypothalamus that send axons down the pititary stalk into POSTERIOR pititary
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Supraoptic nucleus and the paraventricular neucles
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The supraoptic nucleus and the paraventricular nucleus send axons down
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the pituatury stalk into posterior pitutiary
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The supraoptic nucleus and paraventricular nuclus have axons in posterior pituitary taht are in close proximity to a capillar bed this MEANS
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Posterior Pituitary is a TRUE neuroendocrine organ
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The Anterior pitutiary is a TRUE
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endocrine organ
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The posterior pitutiary has neural connection, the anterior pitutiary has
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vascular connections
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Anterior pitutiary has arterial blood vessels that enter a sepicalized region of the hypothalamus AKA
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median eminence
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What happens to vessels in the median eminence
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vessels branch into network of primary cappillaires
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What happens to the primary cappillaires
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the coalesce into long portal veins taht extend down pittuary stalk into anterior pitutiary and form a second capillary network
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What happens to the anterior ptititary capillaires
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coalesce to form viens that exit and enter systemic vascular system
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Where the anterior pititary capillares colalse and exit and enter the systemic vascular system this vascular connection AKA
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hypothalamic-pituitary portal system
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A typical neuroendocrine mechansim---WHat produce posterior pititary hormones
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cell bodes of hypothalmic neurons orginating in supraoptic and parventricular nuclei
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After posterior pituary hormones are produced, what happens
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hormones are transported down neuron axons by anterograde transport to posterior pitutiatry
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Hormones are stored in the posterior pitituary until
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neurons are stimulated to release the hormones directly into the capillar bed of posterior pituitary
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What happens after NEURONS of postieor pitutary are stimulated
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hormones are released DIRECTLY into capillary bed of posterior pittiary where they are taken up and sent to systemic circulation
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What are hormones PRODUCED aned secrted by hypothalamus-posterior pituitary
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Oxytocin and ADH
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Where do anterior hypothalmic neurons orginate
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at various sites in hypothalmus
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After anterior hypothalamic neruons are stimulated what happens
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release hormones into primary capillaries in median eminence of hypothalamus
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Why is the hypothalamus consider a neuroendocrine organ
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both neuronendorcine rlease hormones into blood stream
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What happens after hormones enter the median eminence
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travel down long portal veins into anterior pititary
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What happens after hormones travel down to anterior pittiary
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act on specific cells to simulate OR inhibit hormones
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The anterior pitiary cels produce and secrete anterior pititary hormones into
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the capillar bed for systemic delivery
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What are homoness of anterior pititary
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PAT GG
Prolactin ACTH TSH Growth Hormones Gonoadotropic (FSH, LH) |
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Hormoones of Posterior pitutiary gland
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Oxytocin, ADH both are small peptides
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Principal actions of oxytocin
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contracts pregant uters and REGULATES breast milk release
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What happens to oxytocin receptor on the uterus at the end of pregnancy
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number of receptors increases
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As childbirth nears, streching of the uters and cervix --
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sends afferent neuronal singals to hypothalamus to produce and release oxyotcin
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How does released oxytocin sitmulate uterus
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intnese uterine smooth mucles contraction to intensify labor and stimulate childbirth
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Does oxytocin indcued postpartum uterine contactions also aid in delivery of placent and reduce bleeding
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YES
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What is the primary stimulus for breast milk RELEASE NOT synthesis
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suckling by a nursing baby via affeerent neurons singals to hypothalamus
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What is a secondary simulus for breast milk release
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sensory or physchological stimuli such as a baby crying
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Oxytocin actions of contacting pregant uters and regulates breast milk release is an example of
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POSTIVE feeback reulgation (deparature from tresting conditoin
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Oxytocin does not maintain homeostatis, however ADH
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is major homoestaic function of posterior pitutary
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Principal actions of ADH
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increases water retention by kindeys by increasing water channels in collecting ducts and constirct blood vessels at HIGH concentrations
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ADH causes water retention but NOT
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electrolyte retention
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What is result of ADH
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Decrease urine volume
Increases plasma/ECF volume Decrease plasma/ECF osmolality |
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What are 2 primary regulators of ADH secretion
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Plasma osmolality and blood volume
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What other factors can stimulate ADH secretion besides plasma osmolality and blood volume
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angiotensin, anesthetics, bariturates, and nicotine
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Stimulate ADH secretion does what
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reduces urine production
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What Inhibits ADH secretion
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alcohol (increases urine production)
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What is incresed plamsa/ECF osmolality AKA
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hyperosmolality
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Hyperosmolality does what to cells
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causes them to shrink and send singals to supraoptic nucleus to produce and secrete ADH
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What notices to an increased plasma/ECF osmolality
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osmoreceptors
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Do only small changes in osmolality trigger ADH secretion
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YES
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What % of blood volume loss triggers ADH secretion
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10%
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Loss of >10% of blood volume triggers ADH secretion via
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peripheral volume receptors on afferent neurons, which signal the hypothalamus
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Oxytocin works by a positive feedback mechanism, how does ADH work
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negative feedback mechansim
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What happens to cells with an increase plasma volume
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swells swell--inhibit posterior pitituary, which decreases ADH
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Large blood loss can result in
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HIGH ADH secretion
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What is result of HIGH ADH secretion
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contricts blood vessels
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What is main problems of diabetes insipidus
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insufficient ADH
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Causes of diabetes insipidus
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neurogeneic (injury to hypothalamus/postieor p
Nephrogenic psychogenic (complusive water drinking |
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What are main symptoms of Diabetes insipidius
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insufficient ADH secertion
Polyuria (frequent uriantion) Thrist and Polydipsia Little/No change in plasma osmolality |
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Treatemnt of Diabetes insipidus
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increased water intake and ADH replacement therapy
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What is SIADH syndrome of inappropriate ADH secretion
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continious secretion of large amount of ADH
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Causes of SIADH
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Ecotic release from tumors
CNS disorders Drug-induced |
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Main symptoms fo SIADH
(secifically) |
water retention
adn decreased osmolality--espeically hyponatermia |
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Can hyponatermia be fatal
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YES
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Production and secretion of hormones by anterior pituaitry are contolled largely by
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hormones produced in hypothalamus
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What are the HYPOTALMIC hormones
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CT PGG
Corticotropin-release hormone Thyrotripin-releaseing hormone Prolacin Releasing and inhibiting hormone Gonadotroping releasing hormone Growth hormone releasing hormone and inhibiting hormone |
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What does GnRH (hpyothalmic hormone do
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(+)stimulate FSH and LH
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What doe GHRH (hypothalamic hormone do)
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stimulates GH secretion
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What does SS
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inhibits GH secretion and inhibits TSH
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What does TRH (hypothalmic hormone do)
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stimulates thyroid stimulating hormone
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What does PRH do
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stimualtes prolactin
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What does PIH do
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inhibits prolactin secretion
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What does CRH
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stimulates ACTH
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What cell types in anterior pituitary that produce GH
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somatotropoes
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What cell types in anterior pititatiry produce ACTH
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corticotropes
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What cell types in anterior pitituatry produce TSH
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thyrotropes
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What cell types in anterior pituatry produce Prolactin
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lactotropes
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What cell type in anterior pitutairy produce FSH and LH
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gonadotropes
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FSH and LH do what
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1. Germ cell development and secrete estrogen and progererons and testosterone
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Growth Hormone does what
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Liver and many organs and tissue (protein syntheis, and carb metabolism
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TSH does what
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Thyroid--secretes thyroxine and tridothrine
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What does Prolactin do
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Breasts--breat development and production
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What does ACTH do
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adernal cortex--secretes cortisol
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What are the tropic hormones
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FSH and LH, TSH, and ACTH
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Hypothalamic nuclei and releasing/inhibiting hormone secretion are regulated by 2 NEURAL mechanisms
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Rymthimic/circadian rhythm
Various internal or external signals (temp, pain, pleasure, emotion |
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Neural singals timulate or inhibit hypotlamic hormones which in turns regulates
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endorcrine function
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An example of simple negative feedback regulation is CRH, which is secreted from hypothalmus in response to
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stress or other inputs
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What are CRH stimulates
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ACTH secretion from anterior pititaury
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What does ACTH stimulate
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adrenal cortex to secrete cortisol
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Does cortisol have physiologic actions on tissues
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YES
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Where does negative feedback exist with CRH
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increase plasma levels of cortisol decrease ACTH secretion, and CRH secretion
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Does coritsol exerts a simple direct negative-feedback control over its own secretion
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YES
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Cortisol as drug therapy would cause
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atrophy of adrenal cortex
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What happens when one adrenal cortex is destoryed by disease
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decrease cortisol secretion and decreased plasma cortisol, stimulates increased CRH secretion, and increased ACTH secretion, which increases cortisol secretion of remaining adrenal cortex
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Does homeostatis every return as one adrenal cortex is destoryed by disease
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YES
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What are non-sequence hormone
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a hormones not in hormal sequence, but does influece secretion of hypothalmus and anterior pititutiary
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What is an example of non-seuqnece hormone
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estrogen
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Prolactin is under what type of control
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dual control
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Prolactin action
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breast development and milk production (NOT SECRETION)
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Under normal body conditions of prolactin
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Normal body inhibit hypothalmus and and ihibition by PIH
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What happens to prolactin in pregnacy
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Estrogen stimgulates anterior pititary to overcome PIH, and causes prolactin secretion
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BUT estrogen and progesteron are at HIGH concentrations during pregnacy so
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activate breast development, but INHIBIT milk production
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At birth prolactin levels are very high, but what happens to estrogen and progesterone
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DROP VERY LOW, so stimulates milk production for short period of time
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When estrogen and progesteron levels rapidly drop to very low after child birth, why is milk production only simulated for a short period of time
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bc estrogen stimulation of prolactin is gone
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What does suckling of the breast stimulate
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sensory nerves to release PRH and Oxytocin
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Periodic nursing stimulates prolactin secretion with stimlates
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milk production
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What happens when stop nursing
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sensory stimulation removed, noral PIH inbhitition predominates and milk production stops
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What do Dopamine agoinsts do
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inhibit prolactin secretion--prevent milk production
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What do dopamine antagoinsts do
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enchane prolatin secretion and can lead to galacorhhea
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What is galatorrhea ,a nd from
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unwanted milk prodcution--result from dopamine antagonstis
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Besides prolactin, what else is under dual control
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GH
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What triggers GHRH secretion
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DEEP SLEEP, stres and low blood glucose
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Increasing GHRH stimulates
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Anterior pitiatury to increase GH secretion
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What does increased Plasma GH increase
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Increase Liver IGF1 secretion and plasma levels
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Incresed IGF-1 has negative feedback on
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GH secretion on Anterior pitutitary and GHRH on hypothalamus
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Increased Plasma GH has effects on
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Hypothalamus to increase SS secretions
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What are main sitmulates of GH release
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DEEP sllep, Stress, Low blood glucose, amino accids
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What are main inhibitors of GH release
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REM slepp
High blood glucose concentrations |
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Greatest GH occurs during
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DEEP SLEEP
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Deep sleep is required for adequates GH secretion to stimulate
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growth in children, and promote lean body mass
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Lack of deep sleep in adults can lead to
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decrease GH secretion and LOSS of lean body mass (weight gain)
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What are 3 prinical target tissues of GH
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Skeletal muscle
adipose tissue Liver |
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What effects of GH have on liver
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release IGF-1, increases LINEAR growth, and tissue growth
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What effects of GH have on adipose tissue
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increases fatty acid reelase for energy utilization, and decrease fat deposits
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What effects does GH have on SKM
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increases muscle mass
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What are glucose sparing actions of GH
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Inhibts Glucose uptake in muscle and adipsoe , increase gluconeogenesis in liver, and increase blood glucose
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What happens with hyposecrtion of GH in childhood
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lack of noramal growth and short stature
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What happens with hyposecretion of GH in adulthood
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few symptoms
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What are types of GH deficiency
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Primary and Seondary
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Primary GH deficiency is due to
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anterior pititary dysfunction and decreased GH secretion
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What is secondary GH deficiency due to
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others--hypothalamus liver or releated organs
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Treatment of GH hyposecretion
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GH replacment therapy
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What happens with hypersecretion of GH in children
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gigantism
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How does excess GH cause giantism
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excess secretion of somatomedins, which stimulate cartialge synthesis in epiphseal plates, causes exessive linear growth
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What is hypersecretion of GH in adults
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acromegaly
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Does Acromegaly cause a linear growth pattern
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NO b/c epiphsyeal plates are closed, and insenstiive to hormone stimulation
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What happens in acromegaly in adults
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thickening of bones, connective tisues--growth in hands feed nonone
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Is Acromegaly onset slow and insdious--indications may be
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very slow--notice increase in shoe size
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Can Acromegaly have diabetogenic effects
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YES, b/c GH spares glucose use---increased blood glucose concentrtion
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Treatment of acromegaly
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ademona removed surgically or by radiation
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What is the largest endocrine
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thyroid gland
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Where is the thyriod gland consits of 2 lobes
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just below larnyx--connect by the isthmus
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The thyriod gland is highly vascularized, and has a tremendous capacity
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for growth---to b/c a goiter
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Thyroid gland contains numerous, , and the interior of the follicle is filled with
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follicles, filled with thyroglobulin which is a precursor of thyroid hormone
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T4=
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Thyroxine-princial thyroid hormone secreted into blood
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T3
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Triiodothroine--produce and secretede into blood in lesser amount
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What is 1st step of thyroid hormone synthesis
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biosynthesis of thyroglobulin
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What is biosynthesis of thyroglobulin
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Thyroglobulin is synthesized in RER, carbs added in Golgi complex, and packaged into a vesicle and b/c part of follicular colloid
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What is step 2 of throid hormone synthetsis
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acquistion of iodone
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What is acquistion of iodone
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Secondary Active transport moves iodide into cell against its conectration gradient via a Na+K+ ATPase pump
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What causes the iodone trap
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Secondary active transport
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What is benefit of iodone trap
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iodinde molecules cannot esxape and concentration up to 30x, to compensate for periods of low iodide ingesttion and plasma levels
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What happens afer iodone enters cell
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ungergoes oxidation to I2 by throid perosiase and diffuses into colloid
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What is step 3
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iodination of tyrosine
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What happens in iodination of tyrosine
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Tyroid peroxidases attaches iodine to tyrosine resides on throglobulin
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One iodine to tyrosine residure thyroglobluin produces
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Monoiodotyrosine
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Attachment of 2 iodines produces
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diiodotyrosine DIT or T2
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Are both MIT and DIT part of thyroglobulin
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YES
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What is Step 4
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formation of thyroid hormone percursors
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What happens in formation o f thyroid hormone precursors
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MIT couples with DIT forms T3
DIT couples with DIT form T4 |
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What is T3
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Triiodothronine
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What is T4
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thyroxine
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Are T3 and T4 still atached to thyoglobulin
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YES
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What is Step 5
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Uptake of thyroglobulin into follicle cells
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What happens in uptake of thyroglobulin into follicle cells
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upon stiliumation of follicle cells by TSH, causes endocytosis of thyroglobulin into follicle cell
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What is step 6
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Release of thyroid hormone from throglobulin and secretion into bloodsteam
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What happens in step 6
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Lyosomones bind to folicular cells and cleave of T3 and T4, which diffuse into bloodsteam
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What happens to thyroglobin
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degraded by proteolytic enzyme to aa, and ioniode for reuse
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How are T3 and T4 transported
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bound to plasma proteins
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What are the primary carrier of T3 and T4 in the blood
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Tyroxine Binding globulins and albumin
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B/C Thyroxine Binding globulin has higher affinity for T4, what happens to T3
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moved more rapidly from blood
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Can Both T3 and T4 can diffuse through cell membranes and bind to intracellular receptors and trigger gene expression,
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YES
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What happens to T4 in target tissues
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T4 is converted T3
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What tyroid hormones binds with much stronger affinity and most biological actions
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T3
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What is the primary regulator for thyroid follicle cell activity and thyroid hormone secretion
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TSH
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TSH binds to specfic receptors on
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follicle cells, that are couples to AC and CAMP
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What stimulates every aspect of throid hormone synthesis and secretion in thyroid follicles
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TSH
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What is TSH role on follicle cells
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maintain their size and function
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What does TSH do in HIGH concentration
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cause an enlarged thyroid gland
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Low TSH levels can lead to
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decrease in size and function of thyroid gland
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Primary regulator of TSH
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TRH from hypothalamus
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What is Secondary regulatory of TSH
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SS, which inhibitis TSH
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What triggers TRH to be actived
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decrease body temperate
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TRH then stimulates
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anterior pititaury to release TSH
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TSH acts to
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tyroid gland and release T3 and T4
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What provides negative feedback for tyriod gland
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T3 and T4 inhibit hypothalmus and anterior pititary to decrease secretion of TRH and TSH
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What does INCREASE body temp do
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provides negative feedback to hypothalamus to decrease TRH
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What does decrease body tmeprature do
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Simulates TRH
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Increased iodidie short term does what
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inhibits THYROID GLAND activity directly at thyroid gland (prevents over production of thyroid hormone
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What happens with chronic high iodine
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no effect b/c throid follicle cells adapt
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Decrease iodide short term
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no lasting effects
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Chronic low iodide what happens
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T4 decreases, cuases increase TSH--stimulates thyroid gland to grow and produce more thyroglobulin which continue to fill follicles causing a goiter
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Decreased T3 & T4, and increased TSH means
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hypothyroid state
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Decrease T3 & T4 and decreased TSH indicated
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pititaary or hypothalmus problem
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Increased T3 and T4, and decreased TSH indicates
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hyperthyroid
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Increased T4 and T3 and increased TSH indicates
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pituitary or hypothalmus problem
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What are main actions of Thyroid hormone
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Metabolic actions, and growth and development
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What are the metabolic actions of Thyroid hormone
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BC EF N
increases BMR, and Heat increases carb metabolism increases enzymes in glucose oxidation increases fat metabolism increase Na+K+ ATPase in all cell |
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How does Thyroid hormone prmote normal growth and development
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NS development in fetus and infant
normal bone and muscle growth normal reproductive functions |
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What are permissive actions of thyroid hormone
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up-regulates number of beta-agrenergic receptors, and enchanges action of epi and norepinerhpine is sympathetic NS
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What are 2 types of goiters
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Non-toxic goiter
thyrotoxicosis goiter |
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Hypothroidism is deficieny of thyroid hormone, 2 types
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congential--cretinism
acquired-myxedema |
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When does cretinism occur
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at birth
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What is hypothroidsm in adults
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myxedema--aquired disease
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What is most common cause of hypothroidism in US
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Hashimoto's thyroiditis autoimmune destrution of thyroid
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Hyperthroidism is AKA
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Thyrotoxicosis
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What is most common form of HYPERthroidism
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Graves' disease
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Characteristics of graves disease
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hyperthyroidism
goiter exophthalmos |
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Where is parathyroid hormone
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posterior aspect of thyroid gland
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Paraythoid works by negative feedback how
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Low plasma Ca+ actives, High Ca+ inhibits parathroid secretion
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Whata are 3 target tissues of parathyroid gland
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Bone, Kidney and Intestines
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What are actions of Parathyroid hormone on bone
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PTH stimulates osteoclasts to stimulate bone reabsorption to increase Ca+
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What are actions of PTH on Kidney
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enchanes Ca+ reabsroption by kidneys, and activates vitamin D
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What are action of parathyroid hormone on intestines
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increases calcium absroption from stomach, by kidney's activation of D3
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What diseases causes excessive reabsroption of bone
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hyperparathyroidism
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Where is calcitonin is synthezied
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parafollicluar cells of thyroid gland
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What is action of calcitonin
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lowers plasma calcium levels by inhibiting bone resorption and increase exretion by kidneys
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