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Male sex hormones
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1. Androgens
Types: 1. Natural androgens: – Androsterone and testosterone
2. Synthetic androgens: – Testosterone propionate. – Anabolic steroids: Danazol
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Uses: • Hypogonadism: as hormonal replacement therapy.• For Anabolic effects: –Osteoporosis– Severe burns – To increase lean body mass, muscle strength
• Breast cancer • Hereditary angioedema
1. Natural androgens • Testosterone• Converted to dihydrotestosterone (DHT) in skin,
prostate, seminal vesicles, and epididymus.• I.M. testosterone is used to treat androgen deficiency • Effects: – At puberty 2° sexual characteristics in male.– It increase protein synthesis (anabolism), which
increase muscle and bone mass and strength, affect development of male 2° characteristics.
– They increase hair growth and libido in women. Excessive secretion: masculine effects in women.
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2. Synthetic androgensA. Anabolic steroids• Greater anabolic:androgenic activity• Oxandrolone (anabolic: androgenic=3:1-13-1)
Adverse drug reactions:• Infertility: due to suppressed FSH and LH – Decreased testicular size and function
• Masculinization in women: Hirsutism, deepening of voice, menstrual irregularities
• Hepatic dysfunction, Cholestatic jaundice• Psychotic symptoms
Contraindications:1. Benign prostatic hyperplasia and cancer
prostate.2. Pregnancy.3. Children.4. Liver diseases.
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B. Danazol
Mechanism of action: • Danazol is a synthetic steroid analogue with strong
antigonadotropic activity (inhibits pituitary LH and FSH) and weak androgenic action.
• Inhibits CYP450 enzymes involved in gonadal hormone synthesis
Uses:– Endometriosis– Fibrocystic breast disease– Hereditary angioedema (It occurs due to deficiency of
C1- esterase inhibitor)
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Adverse effects– Acne– Hirsutism–Menstrual irregularities– Hepatotoxicity– Thromboembolism– Teratogenic
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2. Antiandrogens
A. Gonadotropin release inhibitors
B. 5a-reductase inhibitorC. Androgen synthesis
inhibitorsD. Androgen Receptor
blockers
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A. Gonadotropin release inhibitors
• Long acting GnRH analogs– Leuprolide–Goserelin–Nafarelin
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B. 5a-reductase inhibitor• In the prostate, testosterone is converted into
dihydrotestosterone (DHT) by the action of 5a-reductase
• DHT acts on prostate cells to stimulate new growth• Finastride: synthetic testosterone derivative• It inhibits the synthesis of Dihydrotestosterone (DHT)
by inhibiting 5a-reductaseTherapeutic uses:• Benign prostatic hyperplasia• Male pattern baldness
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C. Androgen synthesis inhibitors
• Ketoconazole• It is an antifungal agent.Mechanism of action: • It inhibits gonadal & adrenal steroid synthesis by
inhibiting cholesterol side chain cleavage (inhibits P450SCC).
Adverse effects:• Gynecomastia• hepatotoxicity
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D. Androgen Receptor blockers1. Flutamide, BicalutamideMechanism of action: • They block the action of dihydrotestosterone on testosterone
receptors and inhibit the synthesis of new proteins in prostate and prostate cancer cells.
Uses: • Combined with GnRH analogs to treat inoperable prostate Ca.Adverse effects:– Gynecomastia or nipple tenderness– Diarrhea– Hepatotoxicity – Impotence
2. Cyproterone acetate: – It is a competitive blocker of testosterone receptors. – It is used in male hypersexuality, hirsutism, acne,
male baldness, and cancer prostate.
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