Hypothalamic and Ant pituitary disorders Flashcards
What hypothalamic releasing hormone stimulates release of Prl?
TRH
What 3 factors act on the Anterior pituitary to regulate release of prl? #
TRH+
Dopamine -
Suckling +
Prl acts on two tissues. What are they and what are the actions? #
Breast: breast development, milk production
Hypothalamus: lnegative feedback, GnRH suppression
Somatostatin causes negative feedback for on the anterior pituitary downregulate release of what 2 hormones?
GH, TSH
Dopamine down regulates secretion of what 2 hormones from the anterior pituitary?
TSH, PRL
Name some hormones inhibited by somatostatin.
GH, ADH, thyrotropin(TSH)
What is the clinical syndrome that results from deficiency of GH?
Children: short stature
Adults: varies
What is the clinical syndrome that results from deficiency of FSH?
infertility
What is the clinical syndrome that results from deficiency of LH?
Men: hypogonadism, reduced sperm count
Women: hypogonadism, amenorrhea, oligomenorrhea
What is the clinical syndrome that results from deficiency of TSH?
hypothyroidism
What is the clinical syndrome that results from deficiency of ACTH?
Hypoadrenalism- loss of pigmentation
What is the clinical syndrome that results from deficiency of ADH?
diabetes insipidua
What is the clinical syndrome that results from deficiency of OT?
Failure of milk- let down, failure of uterine contraction, post-partum bleeding?
Why would you give both thyroxine and cortisol to someone who had anterior pituitary deficiency?
Thryoxine increased metabolism and that person can go into adrenal crisis due to the renal insufficiency. Always give cortisol with it.
T or F. Thyroxine is a potent pre-puberty growth stimulator.
T.
How could someone with Sheehan syndrome present? #
Panhypopituitarism- s/s of any or all deficiencies with the most life threatening being ACTH (GIVE CORTISOL), followed by TSH, then FSH/LH, and lastly GH.
What is the most common secretory pituitary tumor?
Prolactin
What is the effect of ant. pit. prolactinoma?
Females: amenorrhea, oligomenorrhea, galactorrhea, infertility, osteopenia,
Males: hypogonadism, decreased libido, galactorrhea, pit. deficiencies
#: Also impotence and gynocomastia in men. Bitemporal hemianopsia.
Cause of cushing’s disease
Excess cortisol. Glucocorticoid therapy, ACTH producing ptiuitary adenoma, adrenocortical tumros, ectopic ACTH production
Cause of acromegaly/gigantism?
GH excess
Clinical effects of hormonal excess of gonadotropins?
visual disturbances, headaches, hypogonadism
Four different things that can cause an elevated PRL
- Hypothalamic dopamine def
- Defective dopamine delivery
- Lactotroph insensitivity to dopamine
- Stimulation of lactotrophs. In primary hypothyroidism there is an increased TRH and TSH that could stimulate lactotrophs.
The serum prolactin concentration is much higher in pt with a _____.
macro-adenoma
What does bromocriptine do to LH and FSH activity in hyperprolactinemia?
Increase in frequency of LH and FSH pulses and an increased mean LH. These pt can become fertile.