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199 Cards in this Set
- Front
- Back
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WHat does the hypothalamus release?
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Corticotropin-releasing hormone (CRH) thyrotropin releasing hormone (TRH), gonadotropin releasing hormone (GnRH), Growth hormone releasing hormone (GHRH), somatostatin
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Pituatary Anterior and post
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Anterior LH, FSH, PRolactin, GH, ACTH, TSH
post: ADH, Oxytocin |
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What do the testes ovary release?
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Testes: testosterone, Estradiol E2, androstenedione, anti-mullerian hormone, inhibin
Ovary: estradiol E2, Progesterone, small amounts of androgens, inhibin |
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what does the placenta release?
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hCG, Human placental lactogen,hPL_, progesterone, estroden, corticotropin releasing hormone
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WHat does the thyroid release
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Thyroxine T4, triiiodothryronine T3, calcitonin
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What does the parathyroid release
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PTH
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Adrenal cortex and medulla release?
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Cortex: cortisol, aldo, dehydroepiandrosterone (DHEA)
medulla: Epinephrine, and norepi |
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Pancrease
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Insulin ( B) glucagon, somatostatin, pancreatic polypeptide, gastrin, VIP vasoactive intestinal peptide
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WHat are the types of hormones?
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Pepetides and proteins
Amino Acid derivatives Steroids |
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What is the range or peptide proteins hormones? size? are they proteolytically cleaved from prehormones are they the largest group
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Range from 3--> 100s , made pre then cleaved, water soluble, largest number of hormones
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WHat are the AMINE Hormones?
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TWo groups
Thyroid hormones Catecholamines made from tyrosine |
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what are steroid hormones derived from?
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CH, lipid soluble, made from acetate CHE stored as lipid droplets
LDL taken from Synthesized not stored |
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WHat are the major types of hormones?
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Androgens- testosterone and Dihydrotestosterone
Estrogen- estradiol and estrone Progestins- progesterone Glucocorticoids- costisol and corTICOSTERONE Mineralocorticoids- aldo and deoxycorticosterone |
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What is the RLS in Steroid synthesis
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Star protein Steriodogenic acute regulatory protein (StAR)
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WHat hormones are hydrophobic and what caries them
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Thyroid and Steroid hormones and bind to specific binding globulins
CBG corticosteroid Binding Globulin --> cortisol SHBG- sex hormone binding globulin- T and estradiol TBG- thyroxine binding globulin- thyroid hormones |
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what is circhoral?
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Short frequency about 1 hour
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What is ultradian
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greater than 1hour less then 24 hr like GnRH or LH
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What is circadian diurnal pulsitile secretion?
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24 hour GH
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monthly pulse?
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Ovarian cycle
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Seasonal pulse?
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Thyroid Hormon
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What is primary and secondary disease?
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1 a problem with the hormone producing gland when you secrete too much of a hormone like CRH and the negative loop from the target organ doesnt affect the hypothalamus
2 a problem external to the hormone producing gland like gland secrecting lots of cortisol so CRH and ACTH are low but still have high cortisol |
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Is ACTH receptors target specific receptor on a few cells? what is an example of general target cell
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YEs and Glucocorticoid
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Can some hormones have a primary receptor but still interact with other receptor?
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YEs like insulin which can bing with less affinity to IGF I or like mineralcorticoid receptors can bind cortisol
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What are the factors which determine target cell specificity and activation?
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blood levels of the hormone
Access and binding of hormone to its receptor free vs bound The addinity of the receptors for the hormone Relative number of receptors on or in the target cell the presence of the appripriate receptor activated affector system--> cell signaling system |
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What are the hormone receptor binding requirments?
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Must be saturable only bind one at a time
Hormone binding must be reversible- on or off state must be related to biological effect - calcitonin must tone down calcium |
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can cell regulate the amount of receptors?
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Yes like ACTH increase cause more receptor or GnRH increases cause dcrease in receptor
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can some receptor only require a small amount of receptors for maximal biological response? do they have spare receptors?
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YEs and yes spare receptor may increase taget cell activation at low level
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WHat are some Nuclear receptors?
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GR- glucocorticoid Receptor
MR- mineralocorticoid receptor PR- progesterone AR- androgen ER and ER b- estrogen TR- thyroid RAR RXR retinoids VDR- vit D |
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What are the two major categoris of membrane receptors?
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1 G-protein linked receptors spaning 7 times interact with G-protein GnRH, LH, FSH, ACTH, TSH
or Enzyme linked- single transmembrane spanning receptor w/o intrinsic tyrosine kindase activity prolactin GH leptin STSRwith guanylyl cyclase activity (ANF) STSR with tyrosine kinase activity - insulin |
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In the G protein what does Gs Gi and Gq activate what interacts with each receptor?
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Gs- Mediates adenylyl cyclase- CRH, GnRH, Calcitonin, ACTH, LH, FSH< TSH, PTH, hCG,
Gi- Mediates adenylyl cyclase inhibition, ang II alpha 2 andrenergic, dopamine Gq- mediates phospholipase C activation- GnRH, GHRH, TRH, somatostatin, Oxytocin, Ang II, alpha 1 andronergic |
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Disease of Endocrinology
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Hormone insensitivity/resistance
ligand defect receptro defects signaling pathway defects |
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what does the Para ventricular Nucleas release?
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TRH, CRH, Somatostatin
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WHat does the Arcuate Nucleas Release
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GnRH
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What does the Ventromedial Nucleus release?
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GHRH
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Does the pituitary release hormone in burstS?
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yes
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What are the Hypothalamic pituitary Axes
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Thyroid, Adrenal, Gonadal, GH, Prolactin
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WHat does the hypothalmic pituitary thyroid axis release? what can inhibit TSH release?
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TRH from pvn of Hypothalamus and binds to TRHR in pituitary then TSH made stimulates t4 major and t3 minor but more active making
Glucocorticoids may suppress HPT axis at hypothalamus |
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So primary hypothyrodism?
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high TRH and TSH but low T4 so lack of negative feedback but you get incraese in prolactic and get galactorrhea
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HP adrenal what does the hypo release? pituitary? role?
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Corticoid releasing hormone which has strong diurnal rhythm more in AM then PM so now you have precursors to ACTH which are Proopiomelanocortin POMC
which in anterior can be ACTH, B-lipotropin or B endorphone and in the intermediate lobe Alpha MSH or B Msh |
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What does cortisol do
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react to stress which then causes more corstisol release which then stops stress and lowers ACTH
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HP gonadal?
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GnRH neurons in olfactory placode and go to hypo thalamus and it is sent in pulse sorelease FSH LH and GnRH stimulated by Norepi and inhibited by Dopamine, seratonin, opiods, CRH
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What does the GnRH slow or fast pulse favor?
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Slow FSH and fast LH
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WHAT gonad hormone has positive feedback?
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Estradiol just prior to ovulation
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What does gonadal inhibin do? males females?
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males sertoli cells females granulosa cells both inhibit FSH
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What does granulosa cell activin stimulate?
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FSH and follistatin which then attenuates activins effect
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what happen if GnRH is continuous?
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reduces gonadotropin secretion and gonadal stimulation used in prostate cancer to downregulate GnRH receptors
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What are the Hypothalmic Releasing Factors
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Somatostatin and GHRH
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what cause Decrease or increase in GH release?
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Decrease- somatostatin, IGS, Obesity, hyperglycemia, pregnancy
Increase- Sleep, stress, sex hormone, starvation, excercise, hypoglycemia |
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WHat does GH do?
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Increase IGF 1 and protein synthesis and lipolysis and decreases glucose uptake
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What is the Inhibitor of the Arcuate Nucleus
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Dopamine
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Prolactin is unique bc?
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In doesnt act on target gland to produce additional hormones that feed back
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What inhibits prolactin
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DOPAMINERGIC NERURONS
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when does PRL rise
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pregnancy and lactation otherwise constant levels
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What impredes portal circulation which therefore increases PRL
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nipple stimulation, stress, intercourse, hypoglycemia, estrogen, TRH, dopamine antagonist
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What is diefferent about the Posterior pituitary hormone secretion?
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It is made in the cell body neuron in hypo and taken in vesicle to synapse and released as needed
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What secrete ADH and OT?
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Both paraventricular and supraoptic nuclei secrete ADH more in SON and OT more in PVN
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What are the ADH OT protein in the cell body?
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Pre hormones
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What does ADH and OT do?
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ADH maintains plasma volume and blood pressure by increasing water reabsorption in distal convoluted tubule vasocontrict and lower body temp and fascilitate memory
OT- increase uterine contractsion and milk let down |
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Do diesease of the Anterior P affect ADH?
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No
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What stimulates ADH?
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Changes in blood osmolarity from osmoreceptor in hypothalmus
ALterations in blood volume Osmoreceptors in left atrium, aortic arch, carotid sinus |
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What are diseases of ADH?
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Diabetes insipidus- water loss bc no action from kidney due to ADH or innapropriate ADH so massive fluid retention
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What does oxytocin stimulate?
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PRL release, contraction . renal and vascular actions like ADH and CNS actions of amnesia and stimulating maternal behavior
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What stimulates GnRH inhibits?
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Epi
Dopa, serotonin, opioids, CRH inhibit |
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What does GnRH stimulate
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LH and FSH in males T and Females Estrogen
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Do sex steroid have a negative feedback for both male and female??
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yes
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What is the only female positive feedback?
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Estradiol + feedback b4 ovulation
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What cells in female and male inhibit FSH
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Sertoli and Granulosa
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WHat stimulates FSH?
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Activin from granulosa cells and Also activate follistatin
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What glycoproteins do gonadotropins release and what do they form dimer or not?
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Dimer with Alpha and B subunit
Alpha CGA gene B- FSH B, LH B, hCG B, TSH B which combine with Alpha to make dimer |
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When do LH and FSH peak in gestation?
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Mid time
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At birth what do babies experience?
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LH FSH growth which is minipuberty testes and ovary gain fxn boys faster
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So at puberty are GnRH pulses fast or slow which hormone gets release first what else rises?
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First FSH (slow pulse) then faster Pulse so LH then DHEA from adrenal rises and you get hair growth
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female ovulation stages? pulses?
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Early follicular 90 min
Late follicular 60-70 min Early luteal 100 min late luteal 200 min |
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How often do ment pulse
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every 2 hours
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What is delayed puberty for men and women?
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Men no testes development age 14
Female breast 13 and menses 15 |
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Precocious Puberty?
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Male b4 9 females b4 8
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Evaluating delayed puberty
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Look at FSH and LH levels
High--> hypergonadotropic hypogonadism--> karyotype Nomal or abnormal Low or Normal ( within range) --> Hypogonadotropic Hypogonadism--> MRI Normal--> hypothalmic cause Abnormal --> pituitary tumor |
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What do you test first for delayed puberty?
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Prolactin, TSH, Testosterone or Estradiol
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What do you test for the 2nd step in delayed puberty
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LH and FSH
high hypergonadotropic hypogonadism --> gonadal failure low--> hypogonadotropic hypogonadism problem with Hypothalamus and pituitary |
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female ovulation stages? pulses?
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Early follicular 90 min
Late follicular 60-70 min Early luteal 100 min late luteal 200 min |
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How often do ment pulse
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every 2 hours
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What is delayed puberty for men and women?
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Men no testes development age 14
Female breast 13 and menses 15 |
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Precocious Puberty?
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Male b4 9 females b4 8
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Evaluating delayed puberty
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Look at FSH and LH levels
High--> hypergonadotropic hypogonadism--> karyotype Nomal or abnormal Low or Normal ( within range) --> Hypogonadotropic Hypogonadism--> MRI Normal--> hypothalmic cause Abnormal --> pituitary tumor |
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What do you test first for delayed puberty?
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Prolactin, TSH, Testosterone or Estradiol
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What do you test for the 2nd step in delayed puberty
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LH and FSH
high hypergonadotropic hypogonadism --> gonadal failure low--> hypogonadotropic hypogonadism problem with Hypothalamus and pituitary |
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what are some causes for hypogonadotropic hypogonadism
What do you treat them with ? |
Anorexia, excercise, stress and idiopathic hypogonadotropic hypogonadism which is just delayed start in GnRH pulse generator
gonadotropin treatment |
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WHat is the treatment for hypergonadotropic hypogonadism (low FSH and LH and low sex steroid)
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donor gametes
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What can cause precocious puberty?
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early activation of the hypothalmic pituitary gonadal axis or a activation froma exogenous source like tumor in ovary and testes or adrenal
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what enzymes to theca cells lack? what cant they produce?
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17-B-Hydroxy steroid DH and aromatase which is needed to make estradiol
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What enxyme are granulosa cells missing
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17alpha hydroxylase so they cant make androstenedione
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So how do theca and granulosa cells interact?
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LH binds to theca cells which make androstenedione this this is taken to granulosa cells which are activated by FSH which take androstenedione to estradiol
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what occurs in the follicular phase?
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rising lh stimulate theca cells which make androstenedione and FSH makes granulosa cells to make estrogen so estrogen acts as a + feedback and then LH and FSH levels rise sharply leading to ovulation
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What occurs in the luteal phase?
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so increased LH receptors on luteinizing cells (theca and granulosa) makes them very sensitive to circulating LH so levels drop
LH stimulates theca cells androsterone and granulosa cells to convert it to estradiol and LH make granulosa cells make lots of progesterone from LDL |
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so how is the cycle started?
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First you have multiple antral follicle growing which have been rescued by FSH then the start growing the fastest growing is dominant and as they grow the gain Lh receptors and the one that is the lasrgest is also the most sensitive to FSH
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What inhibits multiple eggs from ovulating ?
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drop in FSH
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what does FSH stimulate ?
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inhibin B which closes the ovulation window to only one follicle
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what is the most commone ovarian disease?
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Polycystic Ovary Syndrome (PCOS)
infrequesnt ovulations, hyperandrogenism from increase in theca like cells and less estradiol synthesis and have multiple enlarged follicles |
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so what happens in menopaise
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gonadal failure--> no developing follicles no granulosa cells no inhibi or estrogen production no feedback inhibition elevated LH and FSH so hot flashes and bone loss
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which steroid requires two cells for its production?
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Estradiol
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Which steroid requires the enzyme aromatase
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Estradiol and estrone in granulosa cells
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What steroid feeds forward in the H/P
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Estrogen
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Which hormone is regulated by inhibin?
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FSH
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The rise in this hormone helps select antral follicle for the next cycle?
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FSH
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In what part of the cycle does the rise in this hormone lead to follicular selection
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Late luteal early follicular phase
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what is somatomedin? what does it do?
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Insuling like growth factor 1 in liver and growth plate, stimulate growth and responds to GH somatotropin
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what inhibits GH release? stimulates?
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somatostatin (SRIF) g-protein coupled receptor
Ghrelin- released from fasting |
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What is GH bound to in circulation?
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Growth hormone binding protein
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What does GH bind to?
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GH-Receptro which dimerizes and then Janus Kinase phosphorylates and induces stats
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What are the actions of GH?
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Growth anabolic liver and growth plate and muscle growth(positive nitro balance) and energy increase ketogenic in adipocytes increased lypolysis via activation of HSL and anti insulin effect on hepatocytes myocytes and adipocytes so increased gluconeogenesis
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What are the two somatomedins when are they important?
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IGF -2 b4 birth not dependent on GH
IGF-1 after birth mediated by GH |
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WHere is IGF1 produced?
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Liver and growth plates
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WHat is the IGF-1 receoptor?
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It is a tyrosine kinase receptor which phosphorylates (IRS like insulin) and controls gene needed for growth
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what is the GH and IGF1 axis?
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Hypothalamus + from IGF and GH and - from GHRH
Anterior P + from GHRH and - from Somatostatin and IGF |
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what stimulates and suppress GH release
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Stim: sleep, excercise, hypoglycemia, protein malnutrition, starvation, stress
suppress - hyperglycemia fed state REMsleep |
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What mediates bone growth
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IGF-1 and a little from GH
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What is the endocrine regulation of the Growth plate?
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GH- recruits resting chondrocytes
IGF + on all zones Resting zone- proliferative zone- Stimulated by androgens, estrogen, thyroxine inhibited by glucocorticoids Hypertrophic zone- Thyroxine |
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How does IGF-2 work?
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fxn through IGF1 receptors
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What is a newborn disease in newborn related to GH?
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GHD so hypoglycemia at first year of life weight and height deceleration prominent forehead so slow growth
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What is GHD like ?
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Cushings disease since you have ACTH over production and linear growth deceleration
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WHat do sex hormones do to GH
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Estrongen: augment GF mediated IGF1 production
maturation and fusion of Growth plate so if you have aromatase deficiency males dont have growth spurt but experience persistent growth Androgen- dont alter serum GH/IGF1 levels converted to estrogens locally by chondrocyte aromatse androgen insensitivity syndrom Normal growth spurt and adult height |
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GH excess does what?
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Gigatism b4 closure of growth plates
Acromegaly - after GP closure |
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what are some local growth factors? what receptor family do they use?
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Platelet derived growth factors and vascular epithelial growth Factor
they are locally produces and iportant in angiogenesis and can be targets for therapy Nerve growth factor- needed for maintainance and survival of neurons Epidermal growth factor- cell proliferation fxn mechanism unknown Fibroblast growth factor- IMPORTANT IN SOMATIC GROWTH |
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what is the fxn of sertoli cells?
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Provide Sertoli cell barrier to chemicals
secrete luminal fluid including androgen Binding protein Receive stimulation by Testosterone and FSH to increase sperm proliferation and differentiation Secrete inhibin which feeds back to halt FSH secretion Nourish Developing sperm and phagocytose defective sperm secrete mullerian inhibiting substance which causes female duct system to regress |
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what is the blood testes role ?
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protect sperm from antibodies and pathogens
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what do leydig cell make? what does the product feedback on
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TEstosterone from LH stimulation pitutitary and hypothalmus
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What do sertoli cells secrete do ?
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FSH stimulated and make Inhibin and promote spermatogenesis and negative feedback on H/P
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WHAt are the phases of spermatogenesis?
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Spermatogonial phase-
Type A- induced by T at puberty to proliferate cells keep cytoplasmic connection and after several devision can differentiate to type B spermatogonia Type B-divide to give rise to primary spermatocytes Spermatocyte phase meiosis- primary spermatocyte 4c-2n first mitotic division so 4 c DNA crossover occurs at pro I Secondary spermatocytes become spermatids Spermatid Phase spermiogenesis- spermatid to sperm golgi phase cap phase acrosomal phase maturation phase |
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What is the role of the cytoplasmic bridges?
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Wave of synchronized development
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what is the Leydig cell fxn?
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during fetal devel respond to hCG to make testosterone and in puberty LH makes testo
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What does testo act on ?
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sertoli cell to go through spermatogenesis
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What does testosterone production do?
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LDL CH --> Testosterone RLS is StAR
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What enzyme is unique to T production
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17BHSD3 only in leydig cells
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Which enzyme is testis specific?
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17BHSD3
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What enzyme when defective leads to too much androgen production?
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CYP21 21 hydroxylase
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which hormone binds adrogen receptor stronger?
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DHT
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What are the sex steroid binding proteins?
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SHBP and albumin so 75 % in SHBG and 23 in albu and 2 free
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What are the Actions of T
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Increase spermatogenesis, bone growth by epiphasial growth and closure
Nitrogen balance Athletic performance altered skin function |
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what is the role of the ductus epidymis?
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Make sperm motile and concentrate and move to vazy vas
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what is the role of the ejaculatory duct?
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Transport sperm and secretions from seminal vesicles to urethra
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what do the seminal vesicle secretes?
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fructose, ascorbic acid, flobulins to nourish spermatozoa and clotting agents
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What is a marker for prostate cancer?
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PSA levels prostate specific antigen
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What does viagra act on ?
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guanidine phosphodiesterase 5
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what are the 3 levels of sexual development i utero
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Level 1 genetic sex is determined at fertilization x or y
level 2gonadal sex manifest at 6-7 weeks development of primitive ovary or testis testis develop bc SRY which targets sertoli cell level3 phenotypic sex determined by 10-12 weeks DHT needed made in leydig cell from T need 5a reductase |
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what causes adrenal hyperplasia?
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21 hydroxylase deficiency no aldo or corti made
so causes female masculinization female pseudohermaphrodism |
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what occurs in androgen insensitivity ?
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patient xy but have male pseudohermaphrodism so androgen receptor mutated so normal T and DHT just no affect
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when does fetal sexual development occur?
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at 5th week
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In preovulatory Stage what does the LH surges initiate?
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the continuation of meiosis in the oocyte luteinizatin of the granulosa snthesis of progesterone and prostaglandins w/in the follicle
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WHat does progesterone do?
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enhances proteolytic enzyme activity responsible with prostaglandis for digestion and rupture of the follicle wall
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so what happen in ovulation and meiosis?
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after ovulation you get met arrest at II and production of first polar body asymmetrical divisionetx
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Key steps in sperm transport?
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sperm takes 72 days to make and stored in epididymis and can stay in cervix for 5 days and are activated by cervical mucous after separation from seminal fluid which is alkaline and now sperm are propelled into fellopian tubes in minutes acrosomal reaction
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What is the steps to egg transport?
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tubul trasport occurs by ciliary movement secretory fluid flow and SM contraction so oocyte and cumulus are in ampullary isthmic junction within 2-3 minutes of ovulation fertilization takes place in tube and stays for a few days`
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in early pregnancy what rescues the corpus luteum?
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hCG and maintains luteal fxn until the placenta can establish itself
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When does implantation occur?
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5-7 days after fertilization or 2-3 days after the fertilized egg enters the uterine cavity as a morula
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WHat must happen b4 implantation?
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must have hatching of morula from zona pellucida
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What hormone builds up the endometrium?
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PRogesterone
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WHat are the steps to implantation?
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first apposition- addhesion of the lastocyst to the uterin epithelium which is mediated by cytokines and integrin ( adhesion molecules) which interact withextracellular components
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What does the microvilli of the blastocyst do?
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Flatten and interdigitate with the luminal surface
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What does the embryo release/express early in implantation?
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Extracellular matrix components like lamilinfibronectin intergrins
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What does the cytotrophoblast invade and take a source of
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spiral arterioles and MMP regulate cytokines and plasminogen
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what is horomnoal contraceptive?
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The pill progesterone and estrogen or just progesterone iud long acting injectable steroids
hormones inhibit ovulation and cervical mucus thikening and endometrium decreased glandular secretions |
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What are the key roles played by the placenta during pregrancy?
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Acts as the fetal gut in supplying nutrients
Acts and fetal lung Acts as fetal kidney disposes of waste metabolites majore endocrine gland making many steroids and protein hormones that affect both maternal and fetal metabolism |
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WHat are the key steroid and peptide hormones made by placenta
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steroid:
Progesterone Estradiol and estriol Peptide: hCG hPL ( human placental lactogen) and come from hypothalmic peptides Chorionic corticotropin releasing hormone |
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what does hPL do ?
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single chain Poly peptide like prolactin and GH made from syncytiotrophoblast secreted into maternal circulation
In mom increase IGF 1 and increases tissue insulin resistance and causes lypolysis |
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what is hCG like?
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LH
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what does hCG bind to ?
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corpus luteum and fetal testis LH receptors controlled from GnRH
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what does a decline or arrest of hCG indicate? elevated?
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Ectopic pregnancy, miscarriage, fetal demise.
increase trophoblastic disease multiple fetuses |
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what is the hCG fxn
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rescues Corpus luteum and maintains progesterone production critical to maintain endometrium in early pregnancy will promote testosterone production in time of testes development
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What happens to progesteron levels as pregnancy progresses what makes it after 8 weeks
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they rise, placenta
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what does progesterone do ?
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inhibits uterine contraction and prostaglandins production and block tcell mediated immune response
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what happens in phase 1 of labor?
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increase in oxytocin receptors and increase in gap jxn and increase PGand cervical ripening initiated by decrease in progesterone and increase in Estrogen levels and CRH made in placenta
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what enzyme is the placenta defficient in ?
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17a hydroxylase
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what produces estrogens in early and late gestation
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corpus luteum early and syncytiotrophoblast
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what does the fetal adrenal secrete?
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DHEA-s in large quantities and is responsive to ACTH in fetal zone which regresses after birth
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what is a good indicator of fetal well being?
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look at estriol levels
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what are some diseases of low estriol levels?
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fetal death, severe intrauterine growth retardation. fetal adrenal hypoplasia, anencephaly, placental sulfatase deficiency
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What enzyme does the placenta have and what does it removes
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sulfutase and removes sulfur
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what is a placental sulfatase deficiency ?
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X linked, males have ichthyosis a nd mother have low levels of estrogen common and have prolonged pregnancy and hard to dialate cervix
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What happens in phase 2 of labor? what hormone?
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effacement thinning of cervix 2ND STAGE IS EXPULSION
oxytocin increase along with fetal and maternal prostaglandins |
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phase 3 of labor whats involved ?
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oxytocin plays a more important role heremore milk secretion here the uterus is remodelled and the cervix goes back to the non pregnant state
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What are the stages to lactation
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mammogenesis-growth high estrogen,
lactogenesis- progesterone driven first switch to alveolar cells then tight jxn close and milk stored then becomes autocrine to meet supply and demand Glactopoisis- after 9 days so prolactin and oxytocin regulated |
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What do you get during lactation in prolactin levels
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rapid spikes
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what does colostrum contain?
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lactoferrin antibacterial, antibodies,
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what does thyroxine do?
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thyroid hormone modulates growth with a direct effects on growth plates especially hypertrophic chondracytes
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what hormone receptor are the GH ones?
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type 1 cytokine receptor which signals janus kinase and signal transducers and activators of transcription STATs
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how much of the insulin released by the pancreas is degraded in the liver?
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30 %
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what does insulin bind to?
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A-subunit and has a conformationcal change of B sununit with autophosphorylation and activation of tyrosin kindase
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what inhibits glucose uptake?
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liver and fat
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what promots insulin pathway?
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muscle cells
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where does the vast reponse of insulin to remove glucose from blood occur?
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skeletal M, liver, and fat
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what are glut coupled with?
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sodium transport
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What glut protein is regulated by insulin?
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4
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what does insulin in muscle do?
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increases port-prandial glucose uptake and consumption by not during excercise, increase muscle glycogen store and traslocation of glut 4
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what does insulin do in the liver
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massive glucose uptake, activate glucokinase, inactivate glycogen phosphrylase, activate glycogen synthase, reduce gluconeogenesis
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WHat does insulin do in adipose tissue?
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so insulin role is to drive storage for long term so reduced lipolysis and in FA uptake
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what are insulins effects on protein?
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increase uptake of AA
increase protein synthesis increase mRNA increase gene expression, inhibit pprotein breakdown reduce gluconeogenesis |
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what is the primary target of glucagon?
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Liver
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what stimulates glucagon release?
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falling glucose, rising AA and the SNS
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what does leptin promote
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STOP EATING
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