In order to assess the relationship between anabolic steroid administration and gynecomastia, we studied the effects produced by administering nandrolone decanoate and a mixture of propionate, phenilpropionate, isocaproate and testosterone decanoate to bodybuilders during a six month period. The following significant changes occurred: a 53% reduction in serum testosterone; LH and FSH levels were suppressed to 77% and 87%, respectively, in comparison to control values; and although 45% of the subjects showed an increase in serum estradiol levels, no statistically significant differences were found compared with control estradiol levels. With regard to estradiol and androgen receptors, 85% of gynecomastia tissue contained estradiol or androgen receptors, while 40% contained both. The mean values of estradiol and androgen receptors in the cytosol were 65 +/- 10 and 52 +/- 5 fmol/mg protein, respectively. Nuclear androgen and estradiol receptor levels were 33 +/- 7 and +/- 9 fmol/mg protein, respectively. The presence of hormone receptors in gynecomastia receptive cells provides support for the hypothesis that gynecomastia is steroid-dependent.
Side Effects. No studies have specifically investigated the effect of insulin use by nondiabetics for the purpose of increasing muscle mass. However, bodybuilders have used short-acting insulin with high-carbohydrate and high-protein diets to promote muscle growth, and a few case studies have reported negative consequences (Evans & Lynch 2003; Konrad et al. 1998; Dawson & Harrison 1997; Reverter et al. 1994). The primary side effect of insulin use by nondiabetics is hypoglycemia. While this condition is preventable and treatable, most individuals use insulin in secrecy and are discovered only when they are found by friends or family in a state of unconsciousness induced by hypoglycemia. Coma, convulsions and death have been reported in some cases (Evans & Lynch 2003; Konrad et al. 1998; Dawson & Harrison 1997; Reverter et al. 1994).