Ovulation Flashcards
Stigma (as related to ovulation)
-Small protrusion at the apex of a follicle
-Represents a site of deterioration of the follicular wall prior to ovulation.
Hyperemia
7-fold increase in blood flow at ovary
Luteinization
Transformation of follicular cells into luteal tissue
Hypertrophy
Increase in volume
Hyperplasia
Increase in number
Luteolysis
The process whereby luteal tissue undergoes regression and cell death
Know how the secretion of LH are regulated.
-Follicle produces estradiol
-Positive feedback to produce GnRH: Surge center
Know how the secretion of FSH are regulated.
-Follicle produces inhibin and estradiol both decrease the amount of FSH produced
Know how follicle development changes with LH and FSH concentrations: Metestrus
Rising progesterone and stimulates small secretions of FSH
Know how follicle development changes with LH and FSH concentrations: Diestrus Recruitment
-FSH stimulates recruitment of follicles: Growth of a cohort
-The growing cohort of follicles secrete estradiol
-Estradiol inhibits FSH and stimulates LH
Know how follicle development changes with LH and FSH concentrations: Diestrus
-A small selection of follicles develop LH receptors on their granulosa cells
-LH encourages follicle growth and maturation (follicles produce more estradiol as they grow)
Know how follicle development changes with LH and FSH concentrations: Diestrus
-One/two cells claim dominance despite the inhibition of FSH
-A LH surge sets off multiple events shortly before ovulation
Be able to describe/explain the Deterministic model of LH surge
-increased GnRH secretion: required to induce the preovulatory LH surge and thus ovulation.
-Farm Species
Be able to describe/explain the Permissive model of LH surge
-GnRH secretion does not increase: Preovulatory LH surge results from enhanced sensitivity of the pituitary gland to GnRH.
-Humans and Primates
Induced Ovulation
-Reflex
-Rabbits, cats
-Copulation is needed for ovulation:
~Intromission stimulates the surge of LH ovulation
~Ovulation occurs through the neuroendocrine reflex
Spontaneous Ovulation
-Farm animals and Humans
-Copulation or presence of male is not necessary for ovulation to occur
~Controlled by events of estrous or menstrual cycle and not affected by intromission
~Occurs due to endogenous endocrine and neuroendocrine factors
Be able to describe the stimulus and reflex reaction that results in induced ovulation
-Ovulation is stimulated by the neuroendocrine reflex
-Copulation activates a reflex inducing ovulation
-Rabbits, Cat, Ferret, and Mink
Describe the characteristics of large luteal cells luteal cells.
-20-70 micrometers
-Majority of progesterone synthesis/secretion
-Rarely multiply after ovulation
-Increase in volume (3-fold): hypertrophy
-Contain LH receptors: Does NOT respond to LH by increasing progesterone production (Progesterone production DOES NOT INCREASE)
-Formed from granulosa cells
Describe the characteristics of small luteal cells.
-Less than 20 micrometers
-Produce some progesterone
-Increase in number: Hyperplasia (5-fold)
-Contain LH receptors: Respond to LH by increasing progesterone production
-Formed from theca interna
Know which factors are thought to affect the “vigor” of the CL.
Number of cells and vascularization.
