02a: Endocrinology Flashcards
Thyroid tissue arises from (ecto/meso/endo)-derm. And the parafollicular cells, which produce (X), arise from (ecto/meso/endo)-derm.
endoderm
Parafollicular (C) cells produce
X = calcitonin
Neural crest
Adrenal cortex arises from (ecto/meso/endo)-derm. And the adrenal medulla, arises from (ecto/meso/endo)-derm.
Mesoderm;
Neural crest
Normal remnant of thyroglossal duct is:
Foramen cecum
Adenohypophysis derived from (ecto/meso/endo)-derm.
(Anterior pituitary) Oral ectoderm (Rathke pouch)
Which four hormones have the same alpha subunit but different beta subunits?
LH, FSH, TSH, beta-hCG
Proopiomelanocortin (POMC) derivatives:
ACTH, MSH
and beta-endorphin (endogenous opioid)
Which anterior pituitary hormones are basophils?
“B-FLAT”
Basophils - FSH, LH, ACTH, TSH
Which anterior pituitary hormones are acidophils?
Prolactin, GH
Neurohypophysis derived from (ecto/meso/endo)-derm. Where exactly are the hormones made?
Neural ectoderm
Supraoptic (ADH) and paraventricular (oxytocin) nuclei of hypothalamus
Post pituitary: hypothalamic axons terminate on (X) and hormones eventually secreted into (Y).
X = Herring bodies (storage sites) Y = hypophysial vein (and then systemic circulation)
Some cases of inherited (AD) (X) disease are due to mutation in (ant/post) pituitary neurophysins. What’s the mechanism?
X = DI; post pit
Neurophysins carry hormones to post pit from hypothalamus but mutation causes misfolding and removal of proteins from ER (along with hormones)
Insulinoma v. exogenous insulin use v. sulfonylurea use. Which will cause concomitant increase in (X) peptide?
X = C
Insulinoma and sulfonylurea (endogenous insulin being made/secreted)
T/F: Insulin crosses placenta.
False
GLUT-4 on (X) tissues is insulin (dependent/independent).
X = striated muscle and adipose
Dependent (actions of insulin include releasing GLUT4 vesicles for these tissuses; but exercise can also increase GLUT4 expression)
Why might a patient with (Grave’s/Hashimoto’s) present with galactorrhea?
Hashimoto’s (high TRH)
TRH stimulates secretion of TSH and prolactin
Prolactin is structurally homologous to (X). What hormones stimulate/inhibit its release?
X = GH
Stim: TRH
Inhibit: DA
Post-partem “contraception” by breast-feeding occurs due to the action of (X).
X = prolactin
Inhibits GnRH synthesis/release (thus inhibiting ovulation in F and spermatogenesis in M)
T/F: High blood glucose levels will increase secretion of GH.
False - hypoglycemia will (GH is a diabetogenic that increases insulin resistance); negative feedback by glucose
Ghrelin produced by (X) and stimulates (Y)
X = Stomach Y = hunger (orexigenic) AND GH release
Name a genetic disorder with increased ghrelin production
Prader willi
Leptin produced by:
adipose tissue
What symptom would you expect to see in all congenital adrenal enzyme deficiencies?
Skin hyperpigmentation (due to high ACTH stimulation); also both adrenal glands will be enlarged (hence “CAH”)
Male with 17a-hydroxylase deficiency. What would you expect to find on physical exam?
Female outward appearance but blind vagina/lack of internal F genitalia (undescended testes)
Rate limiting step in adrenal steroid synthesis
Cholesterol entry via StAR