General Description of Anabolic Steroids
Anabolic steroids are androgenic and therefore produce androgenic effects in the body. Androgens stimulate myogenesis which is the formation of muscular tissue. Androgens are known to cause hypertrophy of both types (I and II) of muscle fibers however the mechanism of this is not completely understood and there are a few accepted mechanisms through which this may occur. It’s widely understood that supraphysiological doses of testosterone in non-hypogonadal men promotes nitrogen density and increases fat free mass (muscle mass) while at the same time decreasing fat, particularly abdominal fat. The increase in muscle mass is mostly skeletal muscle increases and are likely caused by an increase in the synthesis of muscle proteins or possibly a decline in the breakdown in muscle proteins.[6] It has also been hypothesized[7] that androgens regulate body composition by promoting the commitment of mesenchymal pluripotent cells into myogenic lineages and inhibiting their differentiation into adipogenic lineages. However, androgens may also play an anticatabolic role in inhibiting skeletal muscle atrophy through antiglucocorticoid action independent of the androgen receptor.[8]
The mechanisms of action differ depending on the specific anabolic steroid. Different types of anabolic steroids bind to the androgen receptor to varying degrees depending on their chemical structure. Anabolic steroids such as methandrostenolone do not bind strongly to the androgen receptor and instead directly affect protein synthesis or glycogenolysis: while steroids such as oxandrolone bind tightly to the androgen receptor and act mostly on transcription.
- Brodsky, IG; P Balagopal and KS Nair (1996). Effects of testosterone replacement on muscle mass and muscle protein synthesis in hypogonadal men–a clinical research center study. Journal of Clinical Endocrinology & Metabolism, Vol 81, 3469-3475.
- Singh, Rajan; Jorge N. Artaza, Wayne E. Taylor, Nestor F. Gonzalez-Cadavid and Shalender Bhasin (2003 Nov). “Androgens Stimulate Myogenic Differentiation and Inhibit Adipogenesis in C3H 10T1/2 Pluripotent Cells through an Androgen Receptor-Mediated Pathway.”. Endocrinology. 11 (144): 5081-8. DOI:10.1210/en.2003-0741. PMID 12960001. Retrieved on 2007-02-07.
- Hickson, RC; Czerwinski SM, Falduto MT, Young AP. (1990 June). “Glucocorticoid antagonism by exercise and androgenic-anabolic steroids.”. Med Sci Sports Exerc. 22 (3): 331-340. PMID 2199753. Retrieved on 2006-11-24.
