Endocrinology Exam 1

Exam 1 flashcards IPHY 4440

ductless — release secretory products into bloodstream (glands)

Endocrine

primarily uses ducts that opens onto external or internal surface (not into blood). (eg. GI tract)

exocrine

Which if these is NOT under endocrine function

Mammary gland

What glands are exclusively endocrine in function

Thyroid and Pituitary

Act on same cell that secreted the hormone (note to self)

Autocrine signals

secreted by one cell and diffused to adjacent cell

Paracrine signals

stimulate/inhibit release of tropic hormones w/in anterior pituitary

hypophysiotropic hormones

stimulate production of hormones by another endocrine gland (maintain endocrine tissues)

tropic hormones

exert effects on non-endocrine target tissues.

non-tropic hormones

last hormones in the pathway (feedback to hypothalamus and pituitary)

Negative long loop feedback

pituitary hormones feed back to hypothalamus to modify hypophysiotropic hormones

short loop negative feedback

what type of feedback maintains homeostasis? (drives physiological system toward preprogrammed set point)

Negative feedback

what type of feedback drives a physiological system away from the preprogrammed setpoint?

positive feedback

what type of control anticipates change in physiological system?

feedforward control

what type of pathology arises in the last endocrine gland in a reflex?

primary pathology

what type of dysfunction occurs in the anterior pituitary?

secondary hyper/hyposecretion

dysfunction occurs in the hypothalamus

tertiary pathology

what does the superchiasmatic nucleus(SCN) do?

controls rhythms and cycles of hormones

NAT (aka N-acetyltransferase) converts serotonin into…

N-acetylserotonin

what is the rate limiting enzyme for melatonin

NAT

what inhibits melatonin secretion from the pineal gland?

light-induced activation of the SCN

constant, continuous rate of hormonal release

tonic

pulses of hormonal release

phasic

what is thought to cause idiopathic true precocious puberty?

loss of function in pineal gland from tumor

what types of hormones are stored?

catecholamines, peptides, and amine hormones

where does synthesis and storage of catecholamines occur?

chromaffin cells

what type of bioregulator is a catecholamine?

neurohormone

what is the rate limiting enzyme in catecholamine synthesis

tyrosine hydroxylase

what enzyme turns cholesterol into pregnenolone?

P450-SCC

what enzyme turns pregnenolone into progesterone?

3β-HSD

what enzyme synthesizes cortisol

P450-C11

corticosterone → aldosterone

P450-aldo

testosterone → dihydrotestosterone

5a-reductase

testosterone → estradiol

P450-aro