Reproductive Hormones Flashcards
What is the result of GnRh release from the hypothalamus?
Cause gonadotrophs to release FSH and LH
What happens with sustained GnRH?
Inhibit FSH/LH release
What is the half life of GnRH?
degraded by peptidases in about 4 min.
What inhibits GnRH?
Negative feedback from sex steroids and GnIH
What does LH do in females?
Released in a pulsitive manner and stimulates production of corpus luteum
What is the targets for LH?
Females: Theca cells
Males: Leydig cells
What is the main cause of ovulation?
Large increases in LH
What inhibits LH?
Sustained release of GnRH and negative feedback from sex steroids
What is the structure of LH and where is it made?
Alpha and beta chains and made by gonadotrophs in the pituitary
What does FSH do in females?
Stimulate the growth of Graafian follicles
What is the structure and where is FSH made?
Alpha and Beta chain made by gonadotrophs in the anterior pituitary
What activates FSH?
GnRH released in a pulsative manner and activin
What inhibits FSH?
Sustained release of GnRH and inhibin and negative feedback
What is the half life of FSH?
30-100 minutes
What is the targets of FSH?
Females: granulosa cells
Males: Sertoli cells
What is prolactin?
Protein hormone made in the anterior pituitary by lactotrophs. Similar to growth hormone
What does prolactin do in females?
- Mammogenesis
- Lactogenesis
- Galactopoeisis
- Repro and body effects
What does prolactin do in males?
Sensitize leydig cells to LH potentiating testosterone
What regulates prolactin?
Negatively regulated by dopaminergic neurons in the arcuate nucleus
What is oxytocin?
Peptide hormone made in the hypothalamus and released in the posterior pituitary
What does Oxytocin do in females>
- Smooth muscle contraction in repro organs
- Prostaglandin synthesis
- CNS effects
What does Oxytocin in males?
Contraction of the epididymis and vas deferens and prostaglandin synthesis