Endocrine pharmacology: Female sex hormones Flashcards
Types of female sex hormones
Oestrogen
Progesterone
Androgen
Oestrogen: Fertility
Growth of ovarian follicles
Endometrial growth
Increase in tubal motility and uterine contractions
Oestrogen: Lactation
Stimulation of duct growth
Inhibits milk let-down (prolactin)
Oestrogen: Secondary sexual characteristics
Breast development Female habitus (Skeletal, skin, metabolism) Development of external genitalia
Progesterone: Fertility
Endometrial receptivity
Decrease in fallopian tube motility
Decrease in uterine contractions
Progesterone: Lactation
Stimulation of lobuloalveolar development
Inhibits milk let-down (prolactin)
Progesterone: PMS
Progesterone withdrawal
Hypothalamic-pituitary-ovarian axis
GnRH pulsatile generator is in the arcuate nucleus of the hypothalamus.
GnRH is released into blood stream and travels to anterior pituitary gland.
Anterior pituitary releases FSH and LH.
FSH and LH bind receptors on different target cells in the ovary to release either aoestrogen or progesterone, respectively.
In ovary - FSH
Granulosa cells of the Graafian follicle = Oestrogen
In ovary - LH
Corpus luteum - differentiated granulosa and invasive theca cells = Progesterone and Oestrogen
GnRH
Gonadotropin-Releasing Hormone
FSH
Follicle Stimulating Hormone
LH
Leutinizing Hormone
Ovarian steroidogenesis
Two main pathways (Δ4 and Δ5)
Estradiol and estrone are oestrogen
Pathway depends on tissue type and is influenced by which enzymes are present.
The Ovarian Cycle - Follicular phase
- FSH is increasing due to low ovarian hormone production.
- FSH aids follicular development.
- Follicles produce oestrogen.
- High concentration of oestrogen >48 hours