Repro 3 Flashcards
Menstral Cycle Overview:
Day 1 = _______
What are the three phases in the ovarian cycle?
What are the three phases in the endometrial cycle?
Menstral Cycle Overview:
Day 1 = First day of Menses
Ovarian Cycle:
- Follicular phase: growth of dominant follice
- Ovulatory phase: follicle rupture and release of oocyte
- Luteul Phase: formation of corpus leteum
Endometrial Cycle:
- Menstral Phase
- Proliferative Pjase
- Secretory Phase
Ovarian Cycle Overview:
Primordial follicles reach a peak at ______
Only 10% remaining at puberty
Primordial follicles (oocyte and pregranulosa cells) peak at 20 weeks gestation
Millions of follicles at 24 weeks, less but millions at bith, only half a million at puberty, KEEP DECREASING
Length of the phases of the ovarian cycle
Follicular Phase
Ovulatory Phase
Luteul Phase
Follicular Phase (10-14 days):
at the end of the follicular phase you get the mature follicle called the Grafian follicle
Ovulatory Phase: 1-3 days
Luteal Phase: 14 days
Follicular Phase:
Primordial Follicles: outer layer of ____ plus an ____
(during its primordial phase, the oocyte is arrestes in which phase)
Primary follicles: _____ surrounded by ______
How do oocytes get from primordial follicles to primary follicles? (when does this occur)
Follicular Phase:
Primordial follicles: outer layer of pregranulosa cells with an oocyte
- primordial phase: oocyte arrested in diplotene stage of Meiosis I
Primary follicles: larger oocyte surrounded by cuboidal granulosa cells
Require FSH stimulation to develop from primordial into primary follicle (happens in utero)
Follicular Phase Cont’d:
Secondary Follicles:
- now have ___ cells
- increased number of ____ that become multilayered
- Enlargement of ____
Secondary Follicles:
- now have thecal cells (primary follicles didn’t have any thecal cells)
- increased number of granulosa cells that become multilayered
- Enlargement of oocyte
Tertiary Follicle:
Granulosa cells secrete fluid and create an _____
Granulosa cells closest to oocyte secrete polysaccharides to form the ________
Tertiary Follicle:
Granulosa cells secrete fluid and create an antrum
Granulosa cells closest to oocyte secrete polysaccharides to form the zona pallucida
Dominant Follicle Selection:
Maturation from primary to the _____ follicle (the dominant one) takes _____ days
The initial cohort of follicles that started maturing will start _____ (atresia) except 1
Dominant follicle selection is based on _____
Dominant Follicle Selection:
Maturation from primary to Graffian follicle (dominant one) takes 10-14 days
The initial cohort of follicles that started maturing will start dying (atresia) except 1
Dominant follicle selection is based on FSH sensitivity
_______ follicle is the dominant follicle
Granulosa Cells Stratify to 3 types:
- Mural cells =
- Cumulus cells =
- Antral Cells=
The dominant follice is a _____ follicle (meaning it is arrested at what stage?)
Graffian follicle is the dominant follicle
Granulosa cells stratify to three types:
- Mural cells = farthest from oocyte, most metabolically active making hormones, etc
- Cumulus cells = near oocyte, shed at ovulation
- Antral cells = face antrunm, forms luteul cells after ovulation
Note: the graffian follicle is still a primary oocyte, meaning its arrestesed in diplotene stage of meiosis I
Ovarian Cycle: FOLLICULAR PHASE
Remember, Day 1 = first day of menses
_____ is higher than _____
High ____ recruits a cohort of follicles to enter the follicular phase
Recruited follicles start producing ____ (creating a negative feedback on ____)
RATIO SWITCHES (now ___ is higher)
As FSH levels now decrease, follicles start to die off, and the dominant follicle is the one most ____
Also, the increase in LH causes an increase in _____ (more _____ is being made)
FOLLICULAR PHASE:
Remember, day 1 = first day of menses
FSH it higher than LH at this stage
The high fsh levels start to recruit a cohort of follicles to enter the follicular phase
As the follicles start to grow in size, their granulosa cells start producing inhibin B (negative feedback on FSH)
Then FSH levels start to drop, SWITCH IN RATIO and now LH is higher
As FSH levels decrease, dominant follicle is chosen as one most sensitive to FSH
Also, more LH stimulates the thecal cells to start making steroid hormones (more androsteroinen to make more estradiol) so estradiol increases
Follicular Phase:
After the increase in FSH at the beginning starts to create more follicles,
the follicles produce 2 forms of negative feedback on FSH to create the switch to LH
What are the two forms of negative feedback on FSH
Negative Feedback on FSH:
The growing follicular granulosa cells create inhibin B, which acts as negative feedback on FSH at the pituitary
ALSO, the growing follicles start to produce more estradiol. and that estradiol favors LH over FSH
Two compartment theory of estradiol synthesis:
Thecal cells have ____ receptors, they produce ___
Granulosa cells have ____ receptors
What does FSH do within the granulosa cells:
- *
Two compartment theory of estradiol synthesis:
Thecal cells have LH receptors >>> synthesize androgens (androstenedione enters granulosa cell)
Granulosa cells have BOTH FSH and LH receptors: they produce estradiol from androstenedion:
- FSH:
- stimulates LH receptor expression (important for ovulation LH surge)
- increases aromatase expression in granulosa cells to increase estradiol synthesis
Ovulatory Phase:
Preovulatory Phase: (32-36 hours before): _____
- Switch from negative to positive feedback requires ___ to become at a critical level
- Follicle continues to _____
- The oocyte does what?
Ovulation:
- expulsion of oocyte out of ___
- increased ______
- breakdown of _____
Ovulatory Phase:
Preovulatory Phase: LH Surge
- switch from negative to positive feedback requires estradiol levels to reach a critical threshold
- follicle continues to mature
- oocyte completes meiosis II, continues to Meiosis II and gets arrested in metaphase of meiosis II (meiosis II completes upon fertilization)
Ovulation:
- expulsion of oocyte out of ovary
- increased inflammatory cytokines
- breakdown of ovarian wall
Primary Amenorrhea:
Define the term
What are the common causes?
Primary Ammenorrhea:
Absence of menses in a phenotypic female by 17 yo
Common causes: disoders of sexual determination
Turner’s syndrome
Complete androgen resistance
hormonal disorders in ovaries, adrenal, thyroid HPG axis
Secondary Amenorrhea:
Define the term
Common causes?
Secondary Amenorrhea:
Cessation of menstration for longer than six months
Most common causes: pregnant, lactating, menopause
Others: prolactinoma, panhypoptuitarism
Oligomenorrhea:
Define the term
List the causes
Oligomenorrhea:
Infrequenty periods (cycle length > 35 days)
Most common causes: changes in CNS mechanisms that regulate GnRH release like stress and illness
Changes in body fat composition - very low levels
Intense exercise, weight loss, anorexia