Reproductive endocrinology Flashcards
Male Reproductive Physiology: Prostate
- Seminal fluid
- Alkalinises vagina
- Triggers clotting factors
Male Reproductive Physiology: Seminal Vesicle
- Seminal fluid
- Fructose/Prostaglandins
- Clotting factors
Male Reproductive Physiology: Epididymis & Ductus deferens
- Sperm maturation
- Storage
- Exit
Male Reproductive Physiology: Testes
- Sperm development
- Testosterone
Cells of the Testes: Sertoli Cells
- Blood testes barrier (tight junctions).
- Nourishment of developing sperm.
- Phagocytic.
- Secrete fluid to flush sperm into epididymis.
- Secrete Androgen Binding Protein (ABP) (= sex steroid binding protein) to maintain high testosterone levels in testes.
- SITE OF ACTION OF TESTOSTERONE.
How are sertoli cells arranged?
Sertoli cells are arranged into seminiferous tubules.
Cells of the Testes: Leydig Cells
- Interstitial cells.
- ENDOCRINE cells within connective tissue between seminiferous tubules.
- SYNTHESISE & SECRETE TESTOSTERONE
Label the Cells of the Testes
Describe Spermatogenesis
- Continuous process.
- Single sperm takes 64 days to mature.
- 200 million sperms present at any one time.
Female Reproductive Anatomy: Oviduct
Site of fertilisation
Female Reproductive Anatomy: Ovary
- Female gonad
- Egg development
Female Reproductive Anatomy: Uterus
- Implantation
- Endometrium
What are the three phases of the female reproductive cycle
Three distinct phases
- Follicular phase
- Ovulation
- Luteul phase
Hypothalamic-Pituitary Gonadotrophin (HPG) axis
Hypothalamus (Gonadotropin Releasing Hormone (GnRH)→ Anterior pituitary (Luteinising Hormone (LH)Follicle Stimulating Hormone (FSH))→ Testes/Ovary
Hormonal Control of Testicular Function
Hormonal Control of the Menstrual Cycle: Follicular phase
- LH and FSH stimulate several follicles to grow.
- Follicles secrete low levels of oestradiol – inhibit GnRH from hypothalamus keeping LH and FSH levels low – causes endometrial arteries to constrict resulting in menstruation.
Hormonal Control of the Menstrual Cycle: Ovulation
Growing follicles start to secrete higher levels of oestradiol – stimulates GnRH release from hypothalamus – LH and FSH levels rise which stimulates ovulation – oestradiol also causes endometrium to thicken.
Hormonal Control of the Menstrual Cycle: Luteal phase
LH stimulates Corpus luteum formation after ovulation – Corpus luteum secretes oestradiol and progesterone – block GnRH from hypothalamus – inhibit LH and FSH secretion from pituitary – further development of endometrium to prepare for pregnancy.
Hormonal Control of the Menstrual Cycle: Overview
Pregnancy stops the cycle
Human Chorionic Gonadotrophin (hCG)
- Following implantation – chorion secretes hCG.
- Functionally similar to LH.
- Stimulates and maintains the Corpus luteum.
- Progesterone and oestradiol levels remain high.
- HPG axis remains inhibited.
