Female Reproductive Anatomy & Physiology Flashcards
What are the major components of the hypothalamic-pituitary-gonadal axis?
- GnRH is produced by the hypothalamus
- hypothalamus induces the production of LH/FSH in the anterior pituitary
- LH/FSH act on the ovaries and gonads to produce their respective hormones (estrogen, progesterone, testosterone), which can act as negative feedback and block GnRH production
- kisspeptin can be activated by estrogen to further induce GnRH secretion
What sex hormones are produced in the 2 anatomical sites of the pituitary?
ANTERIOR = FSH, LH
POSTERIOR = oxytocin (stored)
What is the source of GnRH? What is its target? What is the female response?
hypothalamic surge and tonic centers
anterior pituitary
release of FSH and LH
What is the source of FSH? What is its target? What is the female response?
anterior pituitary
ovary granulosa cells
follicular development and estradiol release
What is the source of LH? What is its target? What is the female response?
anterior pituitary
ovary theca internal and luteal cells
- ovulation
- forms corpus luteum
- progesterone release
What is the source of prolactin? What is its target? What is the female response?
anterior pituitary
mammary glands
- lactation
- maternal behavior
- supports CL in the bitch
What is the source of oxytocin? What is its target? What is the female response?
made in hypothalamus, stored in posterior pituitary, and synthesized by CL
myometrium, endometrium, mammary glands
- uterine contractions
- uterine secretion of PGF2alpha
- milk ejection
What is the source of estradiol? What is its target? What is the female response?
granulosa cells of the follicle, placenta
hypothalamus, mammary glands, reproductive tract
- sexual behavior
- secretion of GnRH
- uterine motility
- mucous secretion
What is the source of progesterone? What is its target? What is the female response?
CL and placenta
endo/myometrium, mammary glands, hypothalamus
- inhibits GnRH and reproductive behavior
- promotes pregnancy
What is the source of testosterone? What is its target? What is the female response?
theca internal cells
brain, granulosa cells, skeletal muscle
- estradiol synthesis
- abnormal masculinization
What is the source of inhibin/activin? What is its target? What is the female response?
granulosa cells
anterior pituitary
- INHIBIT = inhibits FSH secretion
- ACTIVIN = stimulates FSH secretion
What is the source of PGF2-alpha? What is its target? What is the female response?
uterine endometrium
CL, myometrium, follicles
- luteolysis
- uterine contraction
- ovulation
What is the source of PGE2? What is its target? What is the female response?
ovary, uterus, embryo
CL, oviduct
- ovulation
- progesterone release from CL
What is the source of human chorionic gonadotropin (hCG)? What is its target? What is the female response?
trophoblast of blastocyst
ovary
production of progesterone by ovary to prepare for pregnancy
What is the source of equine chorionic gonadotropin (eCG)? What is its target? What is the female response?
chorionic girdle cells, endometrial cups
ovary
formation of accessory CLs
What is the source of lactogen? What is its target? What is the female response?
placenta
mammary glands
mammary stimulation
What are the 2 major relevant functions of GnRH (analogs) in veterinary medicine?
- induce cyclicity and ovulation
- treat follicular cysts
What are the 2 major functions of iatrogenic oxytocin?
- induced smooth muscle contractions
- social, maternal, bonding behavior (receptors in brain)