1 - Second Half of Menstrual Cycle Flashcards
What role does LH have, after ovulation, to increase the production of progesteron?
Maintain corpus luteum
Post-ovulation, thecal cells become what cell?
Small lutein cells
What do small lutein cells produce?
Progesterone
Post-ovulation, granulosa cells become what cell?
Large lutein cells
What do large lutein cells produce?
Progesterone
+ little bit of estrogen
In the secretory phase of the uterine cycle, what effect does high progesterone levels have?
Inhibits further proliferation
Stimulates decidualisation (differentiation)
Specifically, what three changes occur with decidualisation?
Tortuous gland development + secretion
Stromal oedema
Maturation of spiral arteries
What change to the cervical mucus does progesterone elicit?
Mucus thickening
Progesterone acts on what endometrial cell to inhibit the effects of estrogen?
PR receptor on stromal cells
In what manner / pattern is the endometrium shed in menstruation?
Staged pattern
What 2 reasons is the endometrium shed in a staged pattern?
Minimise risk of infection and heamorrhage
What term is used to describe this staged shedding pattern?
Zonal shedding
What two processes occur in menstruation?
Vascular changes
Matrix degradation
The 2 processes occur for menstruation to happen?
Vasoconstriction of spiral arteries
Matrix degradation
What effect does vasoconstriction of these spiral arteries result in ?
Subsequent vasodilation as a result of tissue ischaemia.
Mediated by prostaglandins, endothelins, nitric oxide.
Matrix degradation occurs through the expression of what enzyme?
Matrix metalloproteinases
What MMPs do the endometrial stroma produce?
MMP-1, 2, 3
What MMP does the endometrial epithelium produce?
MMP-7
Which hormone are both stromal and epithelial MMPs regulated by?
What effect does falling hormone levels have?
Progesterone
Decreasing progesterone permits action of MMPs.
Invading immune cells produce what two products to aid this process?
MMPs
Cytokines
What cell provides the source for cellular repair following menstruation?
Stromal progenitor cells
Where are stromal progenitor cells found?
Within zona basalis
Histologically, what type of cell is a stromal progenitor cell?
Glandular columnar cell
In the case of pregnancy, which hormone maintains the longevity of the corpus luteum?
hCG
