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Lets get familar with Androgens and there role in the body. Androgens exert their effects in many parts of the body, including reproductive tissues, muscle, bone, hair follicles in the skin, the liver and kidneys, and the haematopoietic, immune and central nervous systems (Mooradian et al., 1987). The androgenic effects of these hormones can be generally considered as those associated with masculanization and the anabolic effects as those associated with protein building in skeletal muscle and bone. In the male foetus, androgens stimulate the development of the Wolffian ducts (epididymis, vas deferens, the seminal vesicles and ejaculatory duct) and the male external genitalia (penis, urethra and scrotum) (Wilson et al., 1981). During puberty, the androgenic effects resulting from increased testicular steroidogenesis are manifested by growth of the testes, external genitalia and the male accessory reproductive glands (prostate, seminal vesicles and bulbourethral), and secretory activity begins. Further, the secondary sexual characteristics manifested during puberty can be divided into those that are a result of androgenic and anabolic effects. The androgenic effects are the enlargement of the larynx causing a deepening of the voice, the growth of terminal hair (in the pubic, axillary and facial regions; in other regions such growth depends on a number of factors), an increase in sebaceous gland activity (can lead to acne), and CNS effects (libido and increased aggression). Anabolic effects are the growth of skeletal muscle and bone, the stimulation of linear growth eventually ceasing due to the closure of the epiphysis. In men, androgens are essential for sustaining reproductive function, and they play an important role in maintaining skeletal muscle and bone, cognitive function and a sense of well-being. The most important androgen secreted is testosterone; in the eugonadal man, the Leydig cells in the testes produce 95% of the testosterone in the body. The ovaries and the adrenal glands (in both sexes) produce very little testosterone but secrete weaker androgens; in particular, dehydroepiandrosterone (DHEA; and its sulpho-conjugate) and androstenedione are of physiological importance in the women, not least because they can undergo peripheral conversion to more potent androgens, for example to testosterone and 5-dihydrotestosterone (DHT). Another weaker endogenous androgen, androstenediol, also binds to oestrogen receptors. The effects of androgens are modulated at cellular level by the steroid-converting enzymes within the particular target tissue. In reproductive target tissues, testosterone can be considered to be a prohormone, being readily converted by 5-reductase to the more potent androgen DHT. In other tissues, such as adipose tissue and parts of the brain, testosterone is converted by aromatase to the oestrogen, oestradiol. In bone, the mechanism of action of the anabolism of androgens has not been entirely elucidated but both a direct effect of testosterone and a mediated effect by aromatization to oestradiol are important (Orwoll, 1996; Zitzmann and Nieschlag, 2004). In the human skeletal muscle (collected less than 12 h post-mortem), 5-reductase activity (either type 1 or 2) is not detectable (Thigpen et al., 1993), so testosterone itself is chiefly binding to the androgen receptor (as supported also by a number of animal studies, mainly in the rat). Aromatase expression and activity is significant in human skeletal muscle (Larionov et al., 2003) but whether the conversion of androgens to oestrogens within this tissue is physiologically important for mediating some of the myotrophic effect of androgens is yet to be determined.