WOMEN Flashcards
(1) The process of puberty
Defined by period first becoming capable of reproducing:
- Maturation of genital organs
- Acceleration of growth
- Occurrence of menarche (onset of menstruation) in female
(1) Puberty driven by 2 processes
1) Gonadarche: Growth and maturation of gonads, leading in female to increaed secretion of sex steroids + initiation of folliculogenesis and ovulation.
2) Adrenarche: Maturation of adrenal cortex with increased secretion of androgens leading to appearance of public head.
(1) Gonadal-hypothalamic-pituitary axis
1) Follicle stimulating hormone (FSH): stimulates development of Follicles
2) Luteinising hormones (LH): Stims ovulation and development of corpus luteum
BOTH stim secretion of oestradiol
(1) Mechanisms underlying puberty
Hypothalamic maturation hypothesis
- Puberty only requires hypothalamic GnRH
- Emphasises direct link CNS and pituitary and hypothalamic GnRH neurons
- Supporting evidence from rhesus macaque.
(1) Role of gonadotropin and the axis
Stims synthesis and secretion of LH and FSH drom gonadotrphs
- LH and FSH stimulate follicle development and secretion of gonadal steroids that feedback to hypothalamus
- Initial feedback is stim producing ovulation then feedback is inhibitory
(1) wat happens during follicular development
Oestradiol and progesterone result in proliferative and secretory changes in endometrium of uterus. Prepares uterus for implantation
(1) How is oestrogen synthesised
Its made from cholesterol and uses 2 cells, Theca interstitial cells then onto Granulosa cell
(1) Effects of steroids on lining of uterus
1) Oestradiol drives endometrial proliferation, extensive vascular remodeling
2) Progesterone in secretory (luteal) phase prepares prior to implantation
3) No hCG = menstruation
(1) What is Corpus Luteum
Forms out of ruptured follicle by extensive reorganisation and Angiogenesis
PROGESTERONE synthesis:
-Maintains endometrium
-Supports pregnancy until placenta takes over
-lutolysis
-hCG stims progesterone production
(1) Menopause
Absence of periods for 12 months
-Increases FSH (due to no feedback) and LH
-Decreased Oestrogen
-Quality and number of follicles lower with age
Symptoms
-Flushes and vaginal dryness
-Oestrogen deficiency causes osteoporosis
Treatment
-Hormone replacement therapy
(2) Effect of knockout Estrogen Receptor
ER-A KO -Obese -Poor mammary development ER-B KO -Poor placental differenciation -Incomplete differenciation of mammary gland during lactation
(2) Effect of knockout Progesterone receptor
PR-B KO -Reduced mammary ductal morphogenesis PR-A KO -Severely impaired ovulation -Impaired implantation -Decidualisation infertility
(2) Decidualisation in pregnancy
1) Embryo selection
2) Controls trophblast invasion
3) Haemostasis
4) Immunomodulation (fert egg half non self, only time immune system allows this)
5) Oxidative stress defences
(2) Effects of placental progesterone and estrogens
Progesterone
-Suppresses myometrial contractions throughout pregnancy
-Promotes formation of mucous plug in cervical canal
-Prepares mammary gands for lactation
Estrogens
-Proiferative effect on uterus and breasts
-Preparation of uterus and cervix for labour
(3) 4 stages of human parturition
Phase 0: Quiescence (Progsterone, prostacycin)
Phase 1: Preparation of labour (Uterotrophins)
Phase 2: Active labour (Uterotonins)
Phase 3: Involution (Uterotonins: Oxyrocin and prostaglandins)
