Androgens and anti androgens and their drugs

Introduction:

Androgens mean 'Male sex hormones'. These are the substance that cause the development of secondary sex characters in the castrated male.

Castration:

Castration is the removal or inactivation of the testicles of a male animal.

Natural androgen is testosterone from male testes which converted into its more potent form 'Dihydrotestosterone' by the enzymatic action of 5 alpha reductase enzyme.

Adult male testes produce 5 - 12 mg testosterone daily.

Adult female ovary produce 0.25 - 0.5 mg testosterone daily.

Pharmacological action : (Testosterone as a prototype)

1. Secondary sex characters and sex organs:

These changes occur in male at puberty-

> growth of genitals - penis, scrotum, seminal vesicles and prostate.

> growth of hairs - pubic, axillary, beard and moustache

> behavioural changes like voice deepen, aggressive in nature, penile erection and increase Physical vigour.

> other changes larynx grow and acne.

2. Testes:

Testosterone required for the normal spermatogenesis and maturation of spermatozoa.

3. Skeleton and skeletal muscle:

It is responsible for the growth of bones and muscles.

4. Erythropoiesis:

Testosterone accelerated the erythropoiesis by increase production of erythropoietin.

Mechanism of action:

1. Testosterone binds with cytoplasmic androgen receptor.

2. Removal of corepressor and attachment of coactivator.

3. Initiates, combining of androgen response element.

4. DNA transcription enhanced, mRNA formed and translocation into the cytoplasmic and start production of protein synthesis.

5. Response generation occur.

Uses:

1. Testicular failure:

Delayed puberty occur in males, hypogonadism

2. AIDs related muscle wasting:

Muscle wasting is the shrinking or weakness of muscle due to reduce in muscle mass.

3. Ageing:

Testosterone level decline in old age men used medication to increase bone and muscles mass to look younger.

4. Idiopathic male infertility:

Male infertility is due to sperm not mature and produce properly, androgen gives for spermatogenesis and maturation of sperm.

Side effects:

> Women administers androgen cause virilization, voice change, excess body hair and menstrual irregularities.

 > Acne, both in male and female.

> Gynaecomastia specially in children.

Anti androgens:

Anti androgens are those drugs which used to inhibit the over secretion of androgen and suppress the gonadal function.

Ultimately LH and FSH secretion reduced and toxicity due to androgens suppressed.