Reproductive Flashcards
Androgens- testosterone
Produced in leydig cells from precursors androstenedione in adrenal glands
Circulated in blood bound to steroid binding hormones
Testosterone gets converted to dihydrotestosterone by 5a reductase enzyme
5a reductase inhibitors used in benign prostate hypertrophy to inhibit testosterone
Effects- descent of testes, growth and sexual maturation at puberty, spermatogenesis, feedback control of gonadotrophin secretion, development of male secondary characteristics, anabolic effect on bone/muscle, neuroprotective effect on CNS/PNS
Oily depot preparation or ily capsule oral preparation
Phosphodiesterase 5 inhibitors - viagra
Sildenafil (viagra), tadalafil, vardenafil.
Increases release of nitric oxide that activates guanylate Cyclase that increases levels of cGMP (smooth muscle relaxer) by inhibiting phosphodiesterase which degrades cGMP
Contraindicated in cardiac as can cause rapid vasodilation and reduced coronary perfusion
Don’t give nitrate products in emergency for angina if viagra taken
Dipoxetine
Used for premature ejaculation
Short acting SSRI
Gonadotrophin releasing hormone
Released from hypothalamus to stimulate pituitary release of FSH and LH
Low doses used to stimulate ovulation, high doses to suppress FSH and LH
Gonadotrophin inhibiting- danazol
Suppress pituitary-ovarian axis and suppress menstruation and inhibit ovulation
Androgen agonist, alters sex hormone metabolism and receptors
Side effects- virilisation, hirsutism, vaginal dryness, hair loss
Contraindications- preg, liver/kidney impairment
Oestrogen
Secreted by ovarian follicles, synthesised from androgens secreted by adrenal glands, corpus luteum, placenta, liver and testes
Oestradol, oestrone, oestriol, metabolised in liver
Used in disorders of menstruation, HRT, prostate cancer, hirsutism
Uses- follicle development, stimulating mid cycle LH surge, stimulating growth of endometrium/ mucous production, retention of salt and fluid, increased coagulopathy, decreased rate of bone reabsorption, inhibiting secretion of FSH/LH- inhibiting ovulation
Side effects- DVT, stroke, can affect BGL’s
Selective oestrogen receptor modulators (SERM)
Raloxifene
Tissue specific modulators that have agonistic properties at some tissues (cardiac, bone, liver, CNS) and antagonistic actions on others ( breast/uterus)
Raloxifene- increases bone mineral density, improves blood lipid profile, reduces bone reabsorption, no stimulation of endometrium or breast tissue
Anti oestrogens - tamoxifen
Fluvestrant- inhibits all oestrogen effects
Tamoxifen- inhibits oestrogen effects except in uterine tissue -Used for breast cancers
Clomiphene- inhibits oestrogen binding one hypothalamus and pituitary reducing negative feedback effects of circulating oestrogen so more GNHR is released. Raised oestrogen levels stimulate ovulation
Used to treat PCOS and infertility
Side effects - multiple preg, ovarian enlargement
Progesterone
Stimulate secretory phase, maintain endometrium, relax uterine muscle, decrease levels of LH/FSH, raise core body temp
Inactive in oral form, needs to be pessary
Synthetic forms given orally
Anti progesterone - mifipristone
Partial agonist that binds to PR’s and prevents activity of endogenous progesterones- blocks LH surge and prevents implantation, sensitises uterus to PG and has antiglucocorticoid activity
Used- endometriosis, leiolyomas, emergency contraception
Used in combo with misoprostal in terminations
Tibolone
Steroid drug for menopause
Protects against bone reabsorption, elevating moods and libido
Classified as gonadomimetic
Oestrogen, anti-oestrogen, progesterone, a d androgenic effects
Combined oral contraception pill
Oestrogen suppresses FSH so decreased mature follicle development and reduced/no ovulation. Progesterone thickens mucous, decreases LH, impairs ovulation and impair tube motility
Contraindicated in hx breast cancer, cardiovascular disease, oestrogen dependant cancers, focal migraine
Smaller contraindications- HT, diabetes, previous cholestasis, undiagnosed bleeding, sickle cell
