Hormones Wu Flashcards
What is the most important structure for selective, high affinity binding to estrogen receptor?
Phenolic A ring
What is the key enzyme in estrogen synthesis?
aromatase
What is the major source of estrogen in premenopausal women?
granulosa cells of ovary
What is the major source of estrogen in men?
adipose tissue
Estrogen’s role in metabolic actions?
Salt and water retention, edema
DEC LDL INC HDL but inc coag factors and HT
Who has the highest risk of osteoporosis?
Smokers who are thin, caucasian, inactive, low calcium intake, family history
Estrogen Hormone replacement therapy increases risks for?
invasive BC, heart attack, stroke, venous thromboembolism. AAAAND MORE
When should estrogens be contraindicated?
estrogen dependent neoplasm, undiagnosed geneital bleeding/liver disease/history of thromboembolic disorder, during pregnancy!
What are two synthetic estrogens?
diethylstilbestrol + ethinyl estradiol
Tamoxifen and Clomiphene are WHAT?
Estrogen receptor competitive antagonists
What role does the stereochemistry play in tamoxifen and clomiphene function?
TRANS- antagonists
CIS- agonist
What role does clomiphene play in humans?
blocks the estrogen receptor, disrupting negative feedback… enlargement of the ovaries! so tx infertility
What should we give someone to treat their estrogen receptor positive, estrogen-dependent breast cancer?
tamoxifen for palliative treatment
What is the MOA of leuprolide?
GnRH are desensitized, leading to decrease in gonadotropin and steroid release. acts as antiestrogen!
What is an example of a steroidal substrate analog to aromatase?
exemestane! acts as suicide inhibitor to irreversibly inactivate aromatase
Non steroidal aromatase inhibitors?
LETROZOLE and ANASTROZOLE! interact with heme groups of CYPS
post menopausal BC and induction of ovulation with infertility
What causes the 1*C temperature rise at midcycle?
Progesterone secretion increase
DRUGS FOR PROGESTINS
medroxyprogesterone, norethindrone, norgestrel, ethynodiol
MOA of mifepristone?
Competitive antag at progesterone and glucocorticoid receptors.
- prevents ovulation by blocking progesterone receptors at pituitary or hypothal
- luteal phase, block progesterone action on the uterus resulting in release of prostaglandins from endometrium + menstrual bleeding\
- increased adrenal steroidogenesis
What drugs are used as abortifacient in early pregnancy?
Mifepristone with prostaglandin
Morning after pill contents-
Norgestrel/ethinyl estradio or straight up norgestrel or single dose 600 mg mifepristone
How do estrogen and progestin interfere with fertility?
INHIBIT OVULATION! suppress plasma concentrations of FSH and LH
Cardiovascular risks when taking contraceptives?
increased risk of thrmboembolism, increased platelet aggregation and accelerated clotting, milk hypertension
How does one decrease their risk of endometrial and cervical cancer when on oral contraceptives?
take estrogen-progesterone combination preparation instead of just estrogen.
what are the three periods of life when testosterone is highest?
embryogenesis
neonatal period
puberty
What is the anabolic effect of testosterone?
Nitrogen retaining activity. all anabolic steroids tested are also androgenic.
Can steroids really make you stronger???
Promote muscle growth in women and immature boys but no benefit at therapeutic doses
What role does testosterone play in the bloooood?
stimulates erythropoietin formation! so use to treat refractory anemia.
What androgen is used to treat endometriosis? why?
DANAZOL!! weak progestin and androgen activity. suppresses ovarian function by inhibiting midcycle surge of LH and FSH
How do we manage hyperplasia and carcinoma of the prostate?
block the synthesis/action of androgens
What is the most effective inhibitor of testosterone synthesis?
GnRH analog LEUPROLIDE– decreased plasma LH and decreased testosterone
MOA Finasteride
Inhibits 5alpha reductase!Q converts tesosterone to DHT
What acts as a competitive antag of DHT for androgen receptor
cyproterone acetate
What two drugs are NON STEROIDAL anti androgens?
comp antag of androgen receptor
flutamide + bicalutamide
SPIRONOLACTONE?? whats the role here?
Compet antag for androgen receptor. treat female hirsutism.
general uses for anti-androgens?
Treat hirsuitism and male-pattern baldness in women, treat men with excessive sex drive, treat precocious puberty in boys
What causes endometriosis?
Excess estrogen created each month
What are two GnRH anaglos for endometriosis?
leuprolide! Nafarelin!!!!
What are uterine fibroids?
benign tumors that grow in muscle layers of the uterus
What meds can we give to shrink fibroids?
leuroplide and nafarelin
OR cetrorelix acetate (GnRH antagonist)
Based on the properties of oxytocin, how can we clinically treat preterm labor?
- increase hydration to power plasma concentration of oxytocin
- give ATOSIBAN oxytocin antagonist!
