Sex Steroids Flashcards
What are the major effects of oestradiol?
Stimulates growth of the endometrium and breast, stimulates productions of progesterone receptors
What are the major effects of progesterone?
Stimulates growth of the endometrium and breast, maintains pregnancy, inhibits production of oestrogen receptors
What are the major effects of testosterone?
Stimulates male characteristics, body hair, deep voice, anabolism, aggression
What are sex steroids synthesised from?
Cholesterol
What are the actions of oestrogen?
Mild anabolic actions, sodium and water retention, raises HDL, lowers LDL, decreases bone resorption, impairs glucose tolerance, increases blood coagulability
What are the side effects of oestrogen?
Breast tenderness, nausea and vomiting, water retention, increased blood coagulability, thromboembolism, endometrial hyperplasia, ovarian metaplasia, breast hyperplasia
What are the actions of progesterone/progestin?
Secretory endometrium, anabolic actions, increases bone mineral density, fluid retention, mood changes, maintenance of pregnancy
What are the side effects of progesterone/progestin?
Weight gain, fluid retention, acne, nausea and vomiting, irritability, depression, PMS, lack of concentration
What are the adverse metabolic effects of testosterone?
Adverse effects on lipid profiles - HDL-C/LDL-C ratio
Hence increased risk of atherosclerotic disease in males
What would oestrogen drugs be bound to in the blood?
Sex hormone binding globule and albumin
True or False:
Progesterone is almost totally metabolised in one passage through the liver
True
Why are sex steroids easily stored in fatty tissue (adipocytes and brain)?
They are lipophilic
What two types do oral contaceptive pills exist as?
COCP - oestrogen + prostestin
POP - progestin only
What is meant by a monophasic combined pill?
Each tablet contains a fixed amount of oestrogen and progestin
What is meant by a biphasic combined pill?
Each tablet contains a fixed amount of oestrogen while the amount of progestin increases in the second half of the cycle
What is meant by a triphasic combined pill?
The amount of oestrogen may be fixed or variable, while the amount of progestin increases in 3 equal phases
What is an example of a 1st generation progestin?
Norethynodrel
What is an example of a 2nd generation progestin?
Levonorgestrel
What is an example of a 3rd generation progestin?
Desogestrel
What is an example of a 4th generation progestin?
Drospirenone (yasmin)
What are some adverse effects of the pill?
Venous thromboembolism, MI, hypertension, headaches, mood swings, increase risk of stroke in women with focal migraine
What drugs interact with the COCP?
Anti-epileptics such as carbamazepine
Rifampicin
St John’s Wort
All increase production of hepatic P450
What are some risks of HRT?
Unopposed oestrogen increases risk of endometrial and ovarian cancers, opposed oestrogen increase risk of breast cancer, increased risk of stroke and IHD, increased risk of VTE
What does tamoxifen do?
Binds to oestrogen receptor in breast tissue and locks oestrogen-stimulated myoepithelial cell division, also causes ovulation induction
Reduces risk of breast cancer
Give an example of an anti-progestin
Mifepristone - partial agonist to progesterone receptor, inhibits progesterone action
Sensitises the uterus to prostaglandins - used in induction of labour
What is an example of an anti-androgen?
Cyproterone - weak progestogenic effect
Partial agonist at the progesterone receptor that competes with dihydrotestosterone
Can be used to treat advanced prostate cancer
What is a SERM? Give an example
Selective Estrogen Receptor Modulator
Example - raloxifene
Protects against oesteoporosis
