Testosterone Flashcards
(25 cards)
Where is testosterone produced?
In the interstitial cells/ leydig cells in the testis in response to LH
FSH promotes what?
spermatogenesis in the presence of testosterone
In target tissues, testosterone is converted into:
more potent androgen Dihydro-testosterone
What converts testosterone into Dihydro-testosterone?
5-alpha reductase
What does testosterone cause?
1) appearance of secondary sexual characteristics at puberty
2) skeletal growth and epiphyseal closure
3) Increase in lean body mass (anabolic effects)
4) metabolic effects and reduction in HDL
5) Promotes growth of prostate and seminal vesicles
6) Feedback inhibition of release of gonadotropins
Androgen replacement in men in Hypogonadal Men:
- methyltestosterone (oral, SL)
- fluoxymesterone (oral)
- Testosterone cypionate (IM)
- testosterone (transdermal, topical gel)
In patients with hypo-pituitarism, replacement therapy should be initiated when?
only after pubertal age
Biophosphates have replaced androgen therapy in treatment of:
male ostoeporosis
Testosterone secretion decreases when?
with age
Testosterone replacement therapy may increase…
lean body mass
Testosterone replacement therapy may increase the risk of what?
Prostatic hyperplasia and cancer
Adverse effects of testosterone therapy are:
- Masculinization in women and prepubertal children
- hirsutism, acne, amenorrhea, clitoral enlargement, deepening of voice
- Alter lipid profile and greatly increase risk of atherosclerosis and heart disease
Testosertone replacement therapy is contraindicated in:
-Pregnancy (teratogenic)
-Hepatic dysfunction (esp. anabolic steroids)
-Prostatic hyperplasia or carcinoma
-Avoid in children
Monitor in pts with renal & cardia disease
GnRH analogs do what?
cause gonadal suppression by inhibiting the gonadotropin release form the anterior pituitary
GnRH analogs are:
1) goserlin
2) nafarelin
3) buserelin
4) leuprolide acetate
Anti-androgens are:
1) Biosynthetic inhibitors (ketoconazole, finasteride)
2) Receptor Antagonists (cyproterone, flutamide, bicalutamide, nilutamide, spironolactone, gossypol)
Ketoconazole inhibits…
gonadal steroid biosynthesis (no clinical applications other than anti-fungal)
Finasteride (Proscar) MOA:
5 alpha reductase inhibitor that prevents conversion of testosterone to dihydrotestosterone (DHT)
Finasteride clincal uses:
BPH, propecia in men and hirsuitism in women
Cyproterone acetate is a what and that treats what?
antiandrogen that treats hirsuitism in women, and in men to decrease sexual drive (sex offenders)
Flutamide (Eulexin) treats what?
prostatic carcinoma
Bicalutamide (Casodex) and Nilutamide (Nilandron) are:
oral anti-androgens used in patients with metastatic carcinoma of the prostate
Spironolactone is a…
aldosterone receptor antagonist and also competes with DHT for binding the androgen receptor
Spironolactone is used in the treatment of…
hirsuitism
