Where is prolactin made in the anterior pituitary?
What is unique about prolactin hormone secretion?
It is continuously secreted until actively inhibited by dopamine.
Does dopamine inhibit prolaction secretion or does it inhibit prolaction synthesis? Or both?
What hormone stimulates prolactin during pregnancy?
high levels of estrogen
Which thyroid condition stimulates prolactin?
HYPOthyroidism (due to increase in TRH which increases TSH to stimulate T4 and T3)
How would pituitary stalk lesions prevent inhibition of prolactin secretion?
The lesions could inhibit dopamine from traveling from hypothalamus to the anterior pituitary and therefore the prolactin cannot be inhibited.
Why does amenorrhea occur in premenopausal women who have high levels of prolactin?
High levels of prolactin inhibit LH and FSH secretion! Therefore, estrogen is suppressed and menses do not occur.
What is the most common compliant from premenopausal women suffering from elevated prolactin?
Inability to get pregnant
What is the most common compliant from men and post-menopausal women suffering from elevated prolactin?
space occupying effects like HA and visual field deficits
Men-erectile dysfunction low sex drive, and man boobies
What is normal serum prolactin?
Can fertility be restored with treatment to the elevated prolactin?
Where is GH converted in IGF-1?
Mainly the liver but other tissues as well
Is the GH still normally secreted in adulthood?
What does GH affect in the body?
Growth of bone and tissue (of course)
Carbs, proteins, and fat metabolism
What stimulates GH release?
hypoglycemia (released 30-45 after blood glucose reaches lowest levels)
LH and FSH play a role during puberty
Which thyroid condition decreases GH secretion?
What hormone increase heart size by causing left ventricular hypertrophy?
How does elevated GH predispose sufferers to atherosclerosis?
increases free fatty acids in the blood
Are most GH producing pituitary adenomas micro or macro?
Macroadenomas (but less than 1% are malignant)
Which hormones close the epiphyseal plates of long bones and stops adults from growing?
Sex steroids (testosterone and estrogen)
What is pituitary apoplexy?
Acute hemorrhage occurs in a preexisting adenoma
What causes the ischemia in Sheehan's syndrome (aka postpartum necrosis)?
vasospasm of hypophyseal (pituitary) vessels as a result of postpartum hemorrhage
What can cause suddend hypotension and CV collapse?
sudden ACTH deficiency
Will a goiter develop without TSH stimulation?
What is the condition when both the pituitary and target organ hormones are low?