Anterior Pituitary Flashcards
what hormones does the anterior pituitary produce? (6)
prolactin, GH, ACTH, FSH, LH, TSH
what hormones does the posterior pituitary secrete and which hypothalamic nuclei are the respective hormones from?
supraoptic –> ADH
paraventricular –> oxytocin
prolactin synthesis and secretion is mainly under tonic inhibitor control by _______ which is made in the ______ and it keeps prolactin at its basal level
dopamine; hypothalamus
what drugs can cause increased prolactin levels? (2)
dopamine antagonists: metoclopramide and risperidone
what is the likely pathogenesis of mild to moderate hyperprolactinemia (25-100 ng/ml range) in the presence of a larger pituitary mass?
nonprolactin-secreting tumor with infundibular stalk compression and inhibition of dopamine transport to the lactotroph
symptoms of hyperprolactinemia in men vs. women
women: menstrual irregularities, galactorrhea, infertility
men: decreased libido
pathogenesis of hypogonadism in men and decrease in menses in women in hyperprolactinemia
increased prolactin inhibits FSH and LH (gonadotropins) release from pituitary
treatment of hyperprolactinemia
dopamine agonist: cabergoline > bromocriptine
where is GH synthesized, stored, and secreted?
anterior pituitary
GH stimulates ______ secretion by the liver
IGF-1
what 2 tests can you order if you suspect acromegaly?
- serum IGF-1: should be increased
2. oral glucose tolerance: if acromegaly, GH will not be suppressed after glucose load
acromegaly: treatment (3)
- transphenoidal surgery
- somatostatin analogs: octreotide, lanreotide
- GH receptor antagonist: pegvisomant
how does a prolactinoma in a postmenopausal woman typically present?
macroprolactinoma: headaches and vision changes
cabergoline: mechanism of action, use
dopamine (D2) receptor agonist; hyperprolactinemia
GH deficiency usually presents with ______ in the neonatal period
hypoglycemia
