Estrogen and Progesterone Flashcards
What estrogen has the most estrogenic action?
Estradiol (E2)
What does LH target in females?
LH acts on Theca cells to synthesize androgen which is aromatized to E1 and E2 in Granulosa cells from FSH action
What does LH target in males?
LH stimulates testosterone production in the Leydig cells
What is the function of inhibins?
Inhibit FSH release
What is the function of activins?
Stimulate release of FSH
What is the function of aromatase?
Converts androgens to estrogen
What type of cervical mucus is secreted under estrogen control?
Thin mucus
What type of mucus is secreted under progesterone control?
Thick mucus
What is the effect of E2 on HDL and LDL?
Increases HDL
Decreases LDL
What are the main clinical uses of estrogens?
- Oral contraceptive
- HRT
- Acne
What is the main SE of estrogen?
Endometrial hyperplasia and increased risk of endometrial carcinoma
Estrogen Contraindications
- Breast and endometrial cancer
- Pregnancy
- Thrombotic disorders
What are SERMs?
Selective Estrogen Receptor Modulators
What are the actions of SERMs?
They bind estrogen receptors throughout the body and can act as an agonist OR antagonist depending on the tissue
Tamoxifen Indications
Use to treat and prevent breast cancer
Tamoxifen MOA
Estrogen receptor antagonist in breast tissue as a partial agonist in endometrium and bone
Tamoxifen SE
- Neoplasm of endometrium
- Hot flashes
- Abnormal menstruation
Tamoxifen Contraindications
- DVT
- Pregnancy
Clomiphene MOA
Estrogen receptor antagonist in the hypothalamus and pituitary and partial agonist in the ovaries which disinhibits the release of GnRH and increases FSH and LH
Clomiphene Indications
Female infertility from an ovulatory disorder
Clomiphene SE
- Thromboembolism
- Ovarian cysts and hypertrophy
- Abdominal discomfort
Raloxifene Indications
Osteoporosis prevention and treatment
Raloxifene MOA
Estrogen receptor agonist in bone and antagonist in the uterus and breast
Fulvestrant Indications
Treat estrogen receptor positive metastatic breast cancer in post-menopausal women
Fulvestrant MOA
Competitively inhibit estrogen binding to receptor and blocks the action of estrogen on its target tissues - pure antagonist
Fulvestrant Contraindication
Pregnancy
What are examples of aromatase inhibitors?
- Anastrozole
- Letrozole
- Exemestane
- Formestane
Anastrozole/Letrozole Indications
Treatment and prevention of estrogen receptor positive early stage, locally advanced metastatic breast cancer
Exemestane/Formestane Indications
Treatment and prevention of estrogen receptor positive early stage, locally advanced metastatic breast cancer
Anastrozole/Letrozole MOA
Competitive inhibition of aromatase
Exemestane/Formestane MOA
Irreversible inhibition of aromatase
What is the main SE of all aromatase inhibitors?
Osteoporosis and fractures
Norgestrel MOA
Alter GnRH pulsing and responsiveness of the anterior pituitary gland to GnRH
Norgestrel Indications
Contraception
Mifepristone MOA
Inhibits progesterone binding to receptor
Mifepristone Indications
Abortion - up to day 49
What is the idea of the combination of progestin with estrogen for HRT?
It is thought that progestin can protect the endometrium from the bad effects of estrogen
Is the effectiveness of the combination OCPs greater than progestin alone?
Still inconclusive
