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;
35 Cards in this Set
- Front
- Back
|
T or F: peptide hormones are stored
|
TRUE
|
|
|
name some peptide hormones
|
pituitary hormones
insulin |
|
|
from what are steroid hormones derived?
|
cholesterol
|
|
|
T or F: steroid hormones are stored
|
FALSE
|
|
|
what controls the secretion of steroid hormones?
|
the rate of synthesis (b/c they are not stored)
|
|
|
From what are thyroid hormone and catecholamines derived?
|
tyrosine
|
|
|
Are amino acid derivative hormones stored?
|
yes
|
|
|
What is the main MOA of peptide hormones?
|
bind cell surface receptors and activate 2nd msgrs
|
|
|
What is the main MOA of steroid hormones?
|
enter target cells to bind nuclear membrane receptors --> binds DNA --> activate genes, etc.
|
|
|
__ is the link b/w the nervous and endocrine systems
|
hypothalamus
|
|
|
the hypothalamus is part of the __
|
posterior forebrain
|
|
|
adenohypophysis -->
|
anterior pituitary
|
|
|
neurohypophysis -->
|
posterior pituitary
|
|
|
what are the anterior pituitary hormones?
|
GH
PRL ACTH TSH FSH LH |
|
|
T or F: The posterior pitutiary makes vasopressin and oxytocin
|
false! these are made in the hypothalamus and travel down neurons and are stored in the posterior pituitary
|
|
|
Thyrotropin -->
|
TSH
|
|
|
Talk about the control of thyroid hormone secretion
|
1. TRH in hypothalamus induces TSH secretion from anterior pituitary
2. TSH travels to thyroid and induces release of T3 and T4 3. T3 and T4 feedback on hypothalamus and pituitary to decrease release stimuli |
|
|
how can you differentiate b/w 2'ary hypothyroidism caused by lack of TSH vs lack of TRH?
|
Give exogenous TRH. If T3 and T4 levels increase, you know the problem is hypothalamic (i.e., TSH is fine)
|
|
|
corticotropin -->
|
ACTH
|
|
|
the main adrenal hormone under pituitary control -->
|
cortisol
|
|
|
discuss control of cortisol secretion
|
1. CRH from hypothalamus induces ACTH release from anterior pituitary.
2. Cortisol released from adrenal gland 3. Cortisol feedsback on pituitary and hypothalamus to shut-down CRH secretion |
|
|
How can you tell if a lesion is in the hypothalamus or pituitary when cortisol levels are low?
|
give exogenous CRH. If cortisol levels rise, you know it's a problem in the hypothalamus (i.e. ACTH is fine)
|
|
|
How can you differentiate b/w pituitary tumors or non-pituitary sources of cortisol secretion in Cushing's?
|
Give exogenous CRH. If you get an ACTH response --> ACTH secreting tumor in pituitary
No ACTH response --> ectopic ACTH production or adrenal cortical tumor |
|
|
What exerts negative feedback on GnRH secretion?
|
E2 or testosterone
|
|
|
How can you induce ovulation or spermatogenesis in pts w/ hypothalamic d/os?
|
Give exogenous GnRH (Gonadorelin)
|
|
|
What are some uses of GnRH superagonists and antagonists such as Leuprolide?
|
contraception
delay puberty in kids w/ precocious puberty control of estrogen dep. uterine dz suppression of sex-steroid dependent tumors |
|
|
What is different about the MOA of GH compared to the other pituitary hormones?
|
It doesn't act on target tissue. It goes to the liver and activates IGF-1 which acts on the target tissues.
|
|
|
What hormone produced in the hypothalamus inhibits GH?
|
somatostatin
|
|
|
what is octreotide?
|
somatostatin analog
|
|
|
what are some uses of somatostatin analogs (octreotide)?
|
1. Rx GH excess (acromegaly)
2. Rx dz of insulin excess (insulinomas) 3. Rx TSH-secreting pituitary tumors 4. Rx VIPomas (diarrhea dz) 5. Reduction of GI motility in chronic diarrhea |
|
|
What is the hypothalamic hormone that causes release of prolactin?
|
there isn't one! It is inhibited by dopamine
|
|
|
what tonically inhibits prolactin secretion by the anterior pituitary?
|
dopamine
|
|
|
suckling by an infant -->
|
inhibits dopamine release in the hypothalamus --> increase prolactin
|
|
|
T or F: Estrogens inhibit prolactin release
|
FALSE
|
|
|
How do you inhibit prolactin secretion?
|
administer dopamine agonists (bromocriptine, cabergoline)
|
