phys- ovulation and menopause Flashcards
second half of the ovarian cycle is called
luteal phase
how is estrogen circulation moderated
by altering it’s binding protein (SHBG)
increase SHBG- estrogen and thyroxine (produced mainly in the follicular phase)
decrease SHBG- progesterone and androgens (produced in the luteal phase)
If the oocyte is not fertilized and implanted, what happens to the corpus luteum?
it degenerates (w/in 14 days) to become the corpus albicans
When does the menstrual phase (menses) of the uterine cycle occur in relation to the ovarian cycle?
14 days after ovulation
(end of luteal phase, beginning of folllicular phase)
which hormone causes the epithelial layer of the vagina to proliferate and also increased vaginal secretions
estrogen
which hormone decreases the proliferation of the epithelial layer of the vagina
progesterone
which hormone increases oxytocin receptors and contractions in the uterus
estrogen
menopause flowchart
super super low follicle pool ⇒ super low estrogen ⇒ increased LH and FSH ⇒ cycle arrest ie MENOPAUSE
ovulation phase feedback is controlled by
estrogen
positive feedback
which hormone is cardioprotective: good for cholesterol, decreases atherosclerosis, and is an arterial vasodilator
estrogen
luteal phase feedback is controlled by
progesterone
negative feedback
what are the effects of LH surge
(5)
- antral follicle becomes graafian follicle
- meisosis is resumed
- enzymes digest follicle so that oocyte can rupture out
- folliclular theca cells become corpus luteum
- increased prostaglandins
proliferative phase days
does it vary?
days 5-14
yes, it varies
what FSH level is indicative of menopause
over 30
which hormone causes the cervical mucous to become thinner, more watery, and more alkaline, while also causing the cervix to become stretchier
estrogen
What has feedback control over FSH and LH gonadotrophs during the follicular phase?
estrogen
during the follicular phase, granulosa and thecal cells secrete increased amounts of ____
which will be stored where
estrogen
stored in the antrum
which hormones causes the epiphysis to close
estrogen
perimenopause flowchart
decreased folliular pool ⇒ decreased inhibin ⇒ increased FSH ⇒ faster follicular maturation ⇒ shorter cycle
then
vastly decreased follicular pool ⇒ decreased estrogen ⇒ delayed positive feedback ⇒ longer cycle
then
insufficient estrogen ⇒ no positive feedback ⇒ anovulation
after estrogen is created, where does it go
part is bound to SHBG (sex hormone binding globulin) and secreted into the blood to exert systemic effects
part stays in the folliclue to help form the antrum
which hormone decreases Na reabosorption
(less bloating)
progesterone
which hormone inhibits body and facial hair growth
while stimulating pubic and axillary growth
estrogen
When does the progestational phase of the uterine cycle occur in relation to the ovarian cycle?
after ovulation (when the corpus luteum is formed) until the corpus luteum degenerates
which hormone is protective from osteoporosis due to:
- increased Ca uptake into bone
- PTH antagonization and decreased resportion
- osteoclast inhibition
estrogen
menstrual phase days
does it vary?
days 0-4
yes, it varies
If the oocyte IS fertilized and implanted, what happens to the corpus luteum?
Who signals this?
continues to grow and produce estrogen and progesterone, becoming the corpus luteum of pregnancy
signaled by the release of HCG by the placenta
follicular phase feedback is controlled by
estrogen
negative feedback
what happens during the progestational phase
progesterone (secreted by the corpus luteum) changes the endometrium into a highly vascularized, glycogen filled tissue
which hormone causes the endometrial glands to develop and differentiate into an actively secreting tissue, forms the placenta, and decreases uterine contractility
progesterone
Which hormones control the follicular phase?
FSH and LH
which are stimulated by Gonadotropin-Releasing Hormone
FSH- low pulse frequency
LH- high pulse frequency
what stimulates the ovarian follicles
FSH and LH
FSH is the most important in the follicular phase though because it stimulates the follicle to mature
What is the follicle that grows more rapidly during the follicular phase to then rupture and release it’s egg?
What is this called?
On what day does this occur?
graafian follicle
ovulation
day 14
which hormone causes the cervix to be less stretchy and makes cervical mucus more acidic and thick
progesterone
Which hormone causes bloating during the menstrual cycle?
and how?
estrogen
by increasing the absorption of salt and water
which hormones increase the permeability, thickness, and vascularity of the endometrium
estrogen
During the follicular phase, what hormonal change causes the ovarian follicle to secrete more estrogen?
the rise in FSH
HOW is estrogen secreted
theca cells convert cholesterol to androgens with the enzyme cholesterol desmolase when stimulated by luteinizing hormone during the follicular phase
androgens move into the nearby granulosa cells
granulosa cells convert androgens to estradiol with the enzyme aromatase when stimulated by FSH
which hormone causes the oocyte to move into the fallopian tube
estrogen
(increases the number of cilia and their rate of beating)
what synthesizes receptors for progesterone on uterine cells
estrogen
which hormone increases the branching of the breast ductal system, and also stimulates the development of lobules and alveoli
progesterone
There are high levels of estrogen in the luteal phase…
how is a second LH surge suppressed?
progesterone via negative feedback
the menstrual cycle is also known as what
endometrial/ uterine cycle
menopause = no menses for ____ (time)
12 months
what happens during the proliferative phase of the uterine cycle?
endometrium repairs itself and proliferates
due to estrogen from newly growing follicles
What cells produce steroids during the luteal phase?
Where do they come from?
When do they become fully functional?
Luteal cells of the corpus luteum
They’re old follicular cells that have transformed to become enlarged, cholesterol filled, highly vascularized hormone producers (luteinization)
become fully functional 4 days after ovulation
what causes menstrual cramps
increased prostaglandins which cause increased uterine contractions
cycles longer than 28 days have a longer ____ phase
proliferative
which hormone causes increased deposition of SQ fat in the hips and breasts
estrogen
WHEN and HOW is progesterone secreted
when- Luteal phase
how- luteal cells (transformed theca and granulosa cells) secrete it
theca cells convert cholesterol to pregnenolone with the enzyme cholesterol desmolase when stimulated by luteinizing hormone
pregnenolone becomes progesterone (by 3 beta hydroxysteroid)
which hormone increases body temp and appetite
progesterone
Which hormones control the luteal phase?
progesterone and estrogen
(secreted from the corpus luteum)
GnRH can be inhibited by what things?
(causing decreased release of LH and FSH)
stress
exercise
illness
endorphins
prolactin
What inhibits the release of FSH and LH in the luteal phase?
progesterone
with an unfertilized egg, as the levels drop (due to the degenerating corpus luteum) the levels declining, causing the levels to begin to rise again at the end, initiating a new cycle
secretory/ progestational phase days
does it vary?
days 15-28
no, it is constant
What triggers ovulation?
rise in LH
first half of the ovarian cycle is called
follicular phase
Increased prostaglandins due to the LH surge causes?
PMS!!!
increased follicular blood flow, wall distensibility, and proteolytic enzymes
What inhibits the release of FSH (specifically)?
Inhibin which is released from granulosa cells when induced by FSH itself
When does the proliferative phase of the uterine cycle occur in relation to the ovarian cycle?
from the last portion of the follicular phase (end of menstruation) to ovulation
after progesterone is created, how does it travel in the blood
bound to CBG (corticosteroid binding globulin)
which hormone increases breast ductal growth, nipple size, pigmentation, and general breath growth
estrogen
required for growth
Which hormones control the ovulation phase?
estrogen and LH
high level of estrogen causes positive feedback and even more estrogen via increased GnRH pulses and increased GnRH receptors
high levels of estrogen cause LH surge at midcycle
(FSH does not rise due to inhibin)
