Lecture 30: Hormone control of male and female reproduction Flashcards
Describe the hormone control of reproduction
GnRH from the hypothalamus causes the release of FSH and LH from the anterior pituitary gland
What is the target organ for LH and FSH?
the gonads
LH and FSH act together to affect what two processes?
gametogenesis
steroidogenesis
What is gametogenesis (specific to males and females)?
sperm production in the testes and ova development in the ovary
What is steroidgenesis?
hormone production
What are the two male hormones produced?
testosterone and inhibin
What are the three female hormones produced?
estrogen, progesterone and inhibin
What does HPG stand for?
hypothalamo-pituitary-gonadal
Describe the HPG axis
There are GnRH neurons in the hypothalamus which project to the ME where they terminate. Here they release GnRH which stimulates the release of LH/FSH from the anterior pituitary gland. These act on the gonads and cause them to release estrogen, progesterone and testosterone
Do the hormones released from the gonads cause positive or negative feedback to the hypothalamus?
it depends
In what way is GnRH released?
in a pulsatile way
Inside the scrotum, there is what two things?
the seminiferous tubules and the interstitium
What percentage of the scrotum is made up of seminiferous tubules?
80%
What percent of the scrotum is made up of the interstitium?
20%
What is in the interstitium?
Leydig cells
What is the main role of the Leydig cells?
to produce testosterone
What is the main role of the seminiferous tubules?
to produce sperm
What the support/nursing cell in the seminiferous tubules?
the Sertoli cells
The sperm are produced in the seminiferous tubules and stored where?
in the epididymis
Describe the process of sperm production
There is a precursor (spermatogonium) which differentiates and matured into a spermatocyte, spermatid and spermatozoa
In the hormonal control of male reproduction, which hormone is released from the hypothalamus?
GnRH
In the hormonal control of male reproduction, GnRH is released from the hypothalamus and stimulates the release of what from the anterior pituitary gland?
LH and FSH
In the hormonal control of male reproduction, what does FSH do?
this acts on the Sertoli cells to stimulate the release of inhibin and to stimulate spermatogenesis
In the hormonal control of male reproduction, what does LH do? What is the effect of this?
this acts on the Leydig cells and causes them to release testosterone which acts locally on the sertoli cells and enters the blood