Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
46 Cards in this Set
- Front
- Back
|
Name hormones released by the hypothalamus
|
- TRH (thyroid-releasing hormone) - GnRH (growth hormone-releasing hormone)
|
|
|
Name 8 hormones released by the pituitary gland
|
- ACTH - Growth hormone - TSH - FSH - LH - Prolactin - Oxytocin - ADH
|
|
|
What hormones are secreted by the thyroid gland?
|
thyroxine (T4) and triiodothyronine (T3)
|
|
|
What hormones are secreted by the pancreas
|
glucagon and insulin
|
|
|
Name hormones secreted by the adrenal gland
|
cortisol, aldosterone, and norepinephrine
|
|
|
What are the 4 structural groups that categorize hormones?
|
1. Peptides and proteins 2. Steroids 3. Amino Acid derivatives 4. Fatty Acid derivatives
|
|
|
What type of structural hormone is insulin?
|
peptide and protein hormone
|
|
|
What are 2 types of hormones derived from the amino acid tyrosine?
|
- thyroid hormones: a double thyrosine with either 3 or 4 iodine atoms - catecholamines: include epinephrine or norepinephrine are used as hormones and neurotransmitters
|
|
|
Name 2 other amino acids and the hormones that they synthesize
|
1. Tryptophan - a precursor to serotonin and the pineal hormone melatonin 2. Glutamic acid - a precursor to histamine
|
|
|
What are eicosanoids?
|
a large group of molecules derived from polyunsaturated fatty acids, such as Arachadonic acid
|
|
|
Name the principal groups of hormones derived from eicosanoids or arachadonic acid?
|
- prostaglandins - prostacyclins - leukotrienes - thromboxanes
|
|
|
What 3 factors determine the concentration of hormones?
|
1. rate of production 2. rate of delivery 3. rate of degradation or elimination
|
|
|
What organs produce thyroid hormone?
|
- thyroid gland - pituitary gland - peripheral muscle
|
|
|
What are the hormones produced by the alpha and beta cells of the pancreas?
|
- alpha cells produce glucagon - beta cells produce insulin
|
|
|
Explain how control of glucose exhibit positive and negative feedback
|
- positive feedback occurs when an increase in blood glucose stimulates the release of insulin - negative feedback occurs when glucose levels fall and the pancreas stops releasing insulin
|
|
|
What hormones stimulate and inhibit secretion of growth hormone?
|
- growth hormone-releasing hormone (GHRH) stimulates secretion of growth hormone - somatostain, released by hypothalamus, inhibits growth hormone
|
|
|
Name a hormone that is secreted when growth hormone binds to receptors in the liver
|
insulin-like growth factor I (IGF-I)
|
|
|
What disorder is caused by an excess of ACTH secretion?
|
Cushing's syndrome
|
|
|
What are physiologic effects of IGF-1?
|
- stimulates proliferation of chondrocytes (cartilage cells), resulting in bone growth - simulates the differentiation and proliferation of myoblasdts - stimulates amino acid uptake and protein synthesis in muscle and other tissues
|
|
|
What are the most common secretory pituitary tumors?
|
prolactinomas
|
|
|
Deficiency in ADH or insevsitivity of the kidneys to ADH can result in what disease state?
|
diabetes insipidus, which is manifested as polyuria and polydispia
|
|
|
Inappropriate secretion of ADH in excess amounts results in what disease state?
|
Syndrome of inappropriate secretion of antidiuretic hormone (SIADH) and causes hyponatremia
|
|
|
What are the 2 general causes of diabetes insipidus?
|
1. Central (or neurogenic) - a failure of the posterior lobe of the pituitary to secrete adequate amounts of ADH 2. Nephrogenic - a failure of the kidney to respond to adequate amounts of circulating ADH
|
|
|
True/False: Small tumors tend to cause and increase of hormone secretion
|
- Small tumors tend to increase hormone production - Large tumors tend to decrease hormone production (tumor becomes space-occupying lesion & compresses and retards hormone production) The correct answer is: True
|
|
|
Where are the hypothalamic-hypophyseal portal veins located?
|
between the capillary beds of the lower hypothalamus and anterior pituitary
|
|
|
What vessel carries hormones from the pituitary gland to the systemic circulation?
|
hypophyseal vein
|
|
|
What are physical manifestations of a large pituitary tumor?
|
- headaches - bitemporal hemianopsia
|
|
|
What are the major target organs of growth hormone?
|
liver and adipose tissue
|
|
|
What is the effect of growth hormone on insulin activity?
|
- growth hormone anti-insulin activity - it supresses the ability of insulin to stimulate uptake of glucose in peripheral tissues - enhances glucose synthesis in the liver - GH also stimulates insulin secretion (leading to hyperinsulinemia)
|
|
|
What is acromegaly?
|
- excessive secretion of growth hormone in adults - causes an overgrowth of bone and connective tissue; leads to coarse features - excessive growth hormone and IGF-1 also leads to metabolic derangements, including glucose intolerance
|
|
|
What are clinical features of acromegaly?
|
- widening of the hands and feet - coarsening of the facial features - frontal sinus enlargement - prominent supra-orbital ridges - mandible frows downward and forward (prognathism)
|
|
|
How is hypersecretion of GH diagnosed?
|
- measure GH levels 2 hours after oral glucose load (normally GH levels should decrease) - if oral glucose test is positive, MRI to localize tumor
|
|
|
What is the treatment for GH secreting tumor?
|
1. Trans-sphenoidal microsurgery (Tx of choice) 2. Radiotherapy (but it takes too long for onset of effects to occur) 3. Medical Managment - use of dopamine agonist (cabergoline), somatostain analogues (octreotide, lacreotide), GH receptor blockers (Pegvisomant)
|
|
|
What is the most common secretory pituitary tumor?
|
prolactinomas
|
|
|
What are signs and symptoms of prolactinomas?
|
- in men, gynecomastia, loss of libido, impotence, and tumor symptoms (headache, visual impairment - in women, increased bilateral discharge (Galactorrhea), Amenorrhea, infertility, & S/S of decreased estrogen (osteopenia, vaginal dryness, hot flashes, irritability)
|
|
|
True/False: Micro-prolactinomas are more common in men
|
False. Micro-prolactinomas are more common in women. Macro-prolactinomas are more common in men The correct answer is: False
|
|
|
What prolactin level usually implies prolactinomas?
|
> 200 ng/mL
|
|
|
What are some causes of small elevation in prolactin levels?
|
- pregnancy - stress - nipple stimulation - drugs (phenothiazines, methyldopa, cimetadine) - hypothyroidism - chronic renal failure - some chest wall lesions
|
|
|
What is the treatment for hyperprolactinemia?
|
1. Bromocriptine (dopamine agaonist) causes shrinkage of the tumor and restores gonadal function and fertility 2. Trans-sphenoidal surgery - used when the patient has visual field abnormalities, neurological symptoms, or when the patient cannot tolerate medical treatment
|
|
|
What is the cause of hyperthyroidism?
|
- caused by excess ciruculating T4 or T3 - 90% of cases are caused by Graves disease, toxic multinodular goiter, toxic solitary goiter
|
|
|
What is the pathophysiological cause of Graves Disease?
|
- results from IgG antibodies against the TSH receptor - antibodies are called thyroid-stimulating antibodies (TSAb)
|
|
|
True/False: Atrial Fib is common in all patients with Graves Disease
|
Atrial fib is rare in young patients but occurs in over 50% of male patients over 60 y/o The correct answer is: False
|
|
|
What are cardinal signs of Graves' disease?
|
- Conjunctival edema and ulceration - Diffuse goiter - Exophtalmos - Increased lacrimation - Lid lag (usually on downard eye movement) - Lid retration - Peri-orbital puffiness - Pretibial myxoedema - Tachycardia with a bounding pulse - Vascular bruit can be heard over these goiters
|
|
|
A 60 y/o patient presents with atrial fib, heart failure, and weight loss. What should the clinician be suspicious of?
|
hyperthyroidism
|
|
|
What are treatment options for hyperthyroidism?
|
1. Anti-thyroid drugs - Carbimazole or methimazole followed by propylthiouracil (PTU) 2. Beta-blocking drugs - for the initial stages of management 3. Sub-total thyroidectomy 4. Radioactive iodine therapy
|
|
|
What are side-effects of thyroidectomy?
|
- hypothyroidism (will have to be on Synthroid) - hypoparathyroidism
|
