Metabolic effects of anabolic steroids.

After 1935 the best method of discovering and measuring the protein-building action of androgenic steroids in humans proved to be metabolic balance studies. In 1955, when anabolic steroids with less androgens were developed, the nitrogen-balance method was used again to evaluate and compare the nitrogen-sparing effect of the various preparations. The findings of the numerous balance studies that were performed are as follows: The injectable 17 beta-esters, such as nandrolone phenylpropionate, nandrolone decanoate and methenolone oenanthate exert a strong anabolic action for several weeks, amounting to 2-2.50 g nitrogen/day, which corresponds to a daily gain of 12-15 g protein or 60-75 g lean body mass. The orally active 17-alkyl derivatives induce a dose-dependent nitrogen-saving effect of the same order. While the drug is being administered, nitrogen-, calcium- and phosphorus-balance studies in osteoporotic patients show calcium and phosphorus retention in most cases. Anabolic steroids can abolish a negative nitrogen balance brought about by the administration of corticosteroids and anti-androgens. They thus possess anti-catabolic properties. Nitrogen loss after surgical procedures and following accidental traumata can be significantly reduced by pre-operative or post-operative treatment with anabolic agents. Comparison of the metabolic balance method with isotope studies showed a satisfactorily positive correlation. Later calcium metabolism studies in osteoporotic patients were mostly performed with various methods such as in vivo neutron activation analysis and osteodensitometry. They confirm the calcium anabolic effect of certain anabolic steroids.