UNIT 4 P3
male reproductive hormone tract
hypothalamus, GnRH, anterior pituitary, FSH and LH, Sertoli cells, inhibin, interstitial cells, testosterone
what produces testosterone
interstitial cells between seminiferous tubules
what supports sperm development
Sertoli cells
what inhibin does
acts as negative feedback on the anterior pituitary
hormone that prostate cancer and BPH are dependent on
testosterone
mechanism that can be blocked to treat BPH
testosterone turning into DHT
how testosterone exhibits "double negative feedback"
it inhibits anterior pituitary and GnRH secretion
female reproductive hormone tract
hypothalamus, GnRH, anterior pituitary, FSH and LH, granulosa cells, estrogen and inhibin
what influences amount of estrogen being produced
amount of granulosa cells
average length of one menstrual cycle
28 days
three phases of menstrual cycle
follicular, ovulatory, luteal
basic function of the follicular phase
stimulate granulosa cells to divide, grow oocyte from primordial follicle to secondary follicle
basic function of the ovulatory phase
enough estrogen builds up to stimulate LH release, causes egg release which leaves corpus luteum behind, corpus luteum takes over estrogen secretion
effects of estrogen on the uterus
growth of myometrium, growth of endometrium
what myometrium is
smooth muscle layer in uterus
what endometrium is
epithelial lining in uterus
basic function of the luteal phase
corpus luteum shifts production to favor progesterone, which stimulates angiogenesis, inhibits myometrium contraction and GnRH secretion, period begins when granulosa cells die off
progesterone function
stimulates angiogenesis, inhibits myometrium contraction, completely inhibits GnRH secretion
what happens if fertilization does not occur
corpus luteum dies, progesterone production stops, capillaries break and endometrium dies, myometrium contracts
how we can stimulate hyperovulation
injections of GnRH
what hormone puberty begins with
GnRH
why menstrual cycle takes a long time
it is heavily dependent on cell division
how birth control pills work
estrogen and progesterone, negative feedback to inhibit ovulation
how plan B works
progesterone only, blocks ovulation and implantation, taken up to 72hrs after sex
RU486/mifepristone
chemical abortion, progesterone antagonist to break down endometrium lining
ELLA
works like mifepristone, progesterone antagonist
IUD
copper or plastic, irritates lining of uterus to block implantation
detected in pregnancy tests
HCG
what must be done in order to rescue the corpus luteum
the embryo must make HCG
"hand-off" that happens in the second trimester
HCG decreases, placenta takes over estrogen and progesterone secretion
what the enlarged uterus pushes up against
liver, stomach, diaphragm, intestines, bladder
changes to mammary glands
compound tubular secretory epithelium proliferate
reason for risk of gestational diabetes
BV increases by 30-50%, so insulin must also increase
how pregnancy affects MAP
BV increases, PR decreases, CO increases, usually MAP increases
what the increased MAP puts a pregnant woman at risk for
hypertension, pre-eclampsia
symptoms of pre-eclampsia
widespread edema, headache
how pre-eclampsia is made worse
protein is taken up by the baby, decreasing osmotic pressure
symptoms of eclampsia
cerebral edema, blurred vision, convulsions, coma, vascular spasm
how pregnancy affects the respiratory system
increases respiratory rate
how pregnancy affects the thyroid
gland enlarges by 40%
what prostaglandins do
stimulate collagenase to digest collagen ropes holding cervix shut
example of a prostaglandin used in medicine
mifeprostol
incompetent cervix
inadequate collagen ropes, cervix dilates too early, miscarriage
CRH hormone pathway
stress, hypothalamus, CRH, anterior pituitary, ACTH, adrenal cortex, glucocorticoids, increase glucose and estrogen, risk of premature delivery
why stress causes risk for premature delivery
increased estrogen causes myometrium to tighten, may cause contractions to begin
Braxton-Hicks contractions
spontaneous depolarization of the uterine smooth muscle
treatments for braxton-hicks
bedrest, calcium channel blockers, beta adrenergic agonists
positive feedback cycle of oxytocin
hypothalamus, posterior pituitary, oxytocin release, myometrium contracts, cervix dilates, hypothalamus is stimulated more
reason for rest periods between contractions
allows blood flow to the baby
epidural
sodium channel blocker injected into epidural space at L1, relatively safe but relief is not immediate
spinal block
injected into subarachnoid space, works faster but may cause cerebral spinal fluid to leak, leading to headache
risk of oxytocin injection to help labor along
may be too much and result in a continual contraction, causing brain damage to the baby