Pituitary&Hypothalamus Flashcards
Which pituitary is larger? Anterior or Posterior? Which is glandular tissue, which is neural tissue?
Anterior is 80% of the pituitary.. Anterior glandular, posterior neural
What are the two hormones of the posterior pituitary?
AntiDiuretic Hormone and Oxytocin
What are the two functions of ADH?
Controls water balance and inhibits diuresis(urine out put)
What are the two functions of oxytocin?
Controls uterine contractions and breast milk let down
What TYPE of hormones are from the hypothalamus? How are they secreted? All at once?
peptide hormones..secreted in pulses
What are the 4 Stimulatory hypothalamic hormones?
TRH(thyrotropinRH), CRH(corticotropinRH), GnRH(gonadotropinRH), and GHRH(growth hormoneRH)
What are the two inhibitory “substances”? What do they inhibit?
dopamine inhibits prolactin, somatostatin inhibits growth hormone
What are the 6 A.P. hormones?
FLAT PG….FSH(follicle stimulatingH), LH(Luteinizing H), ACTH(ArenoCorticoTropicH),
What is the target for TSH?
thyroid
What is the target for ACTH?
adrenal CORTEX
What is the target for FSH?
ovary/testes
What is the target for LH?
ovary/testes
What are the targets for GH?
liver, all tissues
What is the target for Prolactin?
Breast
What is the thyroid feedback loop?
TRH–>TSH–>T4(thyroxine) and T3 (triiodothyronine)
What is the adrenal feedback loop?
CRH (WHY is it not ACRH???)–>ACTH–>Cortisol
What is the gonad feedback loop? What is the protein messenger that starts this whole process?
GnRH—>FSH/LH—>Estrogen & Testosterone…Kisspeptin
What is the growth feedback loop? What inhibits it again?
GHRH–>GH–>IGF-1(insulin-like growth factor-1)…Somatostatin inhibits GHRH
What is the UNUSUAL feedback loop for Prolactin?
Dopamine BLOCKS Prolactin when milk not needed…When milk is needed: suckling BLOCKS dopamine. Now prolactin can produce milk
Which structure is compromised in PRIMARY disease? What is the outcome?
the target gland.. the hypothalamus stimulates more “target gland hormone” decreased
Which structure is compromised in SECONDARY disease? What is the outcome?
The pituitary is compromised…Tells the hypothalamus to stimulate more
Which structure is compromised in TERTIARY disease?
The hypothalamus is compromised…Low hormone everywhere..
What is the end result of excess TSH? (very rare)
Hyperthyroidism
What is the name of the disease when there is excess ACTH?
Increased cortisol= cushing’s disease
What is the syndrome caused by too much GH?
Acromegaly (gigantism)
What is the cause of headaches due to a pituitary tumor?
Stretched dura
What are two treatment options for a pituitary tumor?
Surgery, radiation therapy
How do we treat excess pituitary hormone? Aside: do pituitary tumors usually produce hormones?
Inhibit pituitary secretion, pit hormone receptor against. Aside: No, pituitary hormones usually don’t produce hormones
How do we treat a pituitary hormone deficiency? 2 hormones to replace…
1.replace target glands hormones and 2. replace pituitary hormone
If there is a mass present, which pituitary hormones go first?
GH, FSH, and LH
Which pituitary hormone is gone if the pituitary stock is compromised?
Prolactin! (Dopamine inhibition is lost)
What two hormones(same loop)are deficient if the pt can’t handle medical stress?
ACTH and Cortisol
What two hormones (same loop) are deficient for hypothyroidism?
TSH & thyroid hormones (T4 &T3)
What Four hormones (same loop) are deficient if there is no menses, impotence, infertility, and low libido?
Low FSH, LH, Estrogen, Testosterone
What is hormone is deficient if there is no lactation?
low prolactin
What two hormones (same loop) are deficient in growth failure in children?
Low GH and IGF-1
What is the only real ODD cause of high prolactin (that has to do with the thyroid)?
High TRH = High prolactin (why?)
What type of drug can you administer to treat high prolactin?
A dopamine agonist
What happens with insulin with too much GH?
Insulin uptake is lowered!
What is an acral tissue?
a tip or extremity: forehead, nose, chin, hands, feet
What is acromalgy before pooberty? Are the bone changes reversible?
gigantism.. Bone changes are irreversable
When testing for acromegaly, what will happen to GH after an oral glucose load?
GH INCREASES above 1
What is typically the first treatment for acromegaly?
Surgery
What two drugs can be taken to slow down the effects of acromagaly?
- Somatostatin (to suppress the release of GH) 2. GH receptor antagonist (to block the GH receptors)
