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Androgens agonists and antagonists. What are androgens ?. Steroid derived from cholesterol found in males and females Androgens produced by testes: Testesterone (principal one) Dihydrotesterone Dehydroepiandrosterone Androstenedione. Where is test. Produced?. Testes Adrenal glamd
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What are androgens ? • Steroid derived from cholesterol found in males and females • Androgens produced by testes: • Testesterone (principal one) • Dihydrotesterone • Dehydroepiandrosterone • Androstenedione
Where is test. Produced? • Testes • Adrenal glamd • Ovaries
Test. Produced from: • Progesterone • Dihydroepiandrosterone
Physiological effects of androgens • Anabolic effects: • Increase body growth • Muscle mass • Red blood cells production • Androgenic effects • Growth of larynx and skeleton • Facial hair • Darkening skin
Synthetic androgens • Testosterone cypionate • Oxandrolone • Stanozolol • Fluoxymesterone
Route of administration • Injection • Some can given orally like oxandrolon • All of them have significant first pass effect • Hepatotoxic
Clinical uses • Replacement therapy in male hypogonadism • Promote growth in prepubertal boys
Toxicity of synthetic androgens • Behavioral effects • Aggressiveness • Hostility • Increase LDL\HDL ratio • Stunted growth due to premature closure of epiphyseal plates • In women:hairsutism,acne,clitoral enlargement • In males decrease the spermatogenesis,testicularatrophy,prostatic hypertrophy ,acne gynecomastia
Androgen antagonists • GnRH (which method of adm.? • Receptor inhibitors • Flutamide • Cyproterone • Steroid synthesis inhibitor • Ketoconazole • Spironolactone • 5-alpha reductase inhibitor • Finasteride
Receptor inhibitors Cyproterone • Flutamide • In combination with GnRH analogue to treat prostate cancer
Receptor inhibitors • Cyproterone • Used to treat hairsutism in women • In combination with estrogens as OC
Synthesis inhibitor • Ketoconazole • Inhibit CYP enzymes in adrenal gland • Not useful in females suffering from increased androgens • No promosing results in prostatic hypertrophy • Side effect:review
5 –alpha reductase inhibitor • Finasteride • In combination with GnRH analogue or alone to treat prostate cancer • Benign prostatic hypertrophy5mg\d • Hairsutism 1mg\day • Propecia :frontal hair loss • Side effects • Antiandrogenic SE • Erectile dysfunction • Hepatitis • Teratogenicity
Drugs used to treat erectile dysfunction • Sildenafil (viagra) • Vardenafil (levitera) • Tadalafil (cialis)
Mechanism of action • Phosphodiesterase -5 inhibitor • Increase cGMP • Activate nitric oxide synthase release NO • Relaxation of corpora carvenosa
Side effects • Headache • Flushing • Alteration in color vision • Pirapism • In combination with nitrates cause hypotension