Experimental Assessment of Additional Hormonal Activity of the Pregnane-Steroid Gestagen Gestobutanoyl

The ability of gestobutanoyl, a pregnane steroid with progestogenic activity, to exhibit additional glucocorticoid, mineralocorticoid, antiandrogenic, and estrogenic effects in rats has been studied. It was found that gestobutanoyl did not have estrogenic activity because it did not increase the weight of the uterus with prolonged (30 d) administration at a therapeutic dose of 0.25 mg/kg and doses 10 and 100 times higher. Gestobutanoyl at a dose of 2.5 mg/kg for 30 d did not show glucocorticoid activity because the thymus mass did not change. However, the thymus mass decreased by 25% (p <= 0.05) when gestobutanoyl was administered at a dose 100 times higher (25 mg/kg) than the therapeutic dose. Gestobutanoyl at a dose of 2.5 mg/kg reduced the expression of androgen receptor (AR) mRNA in the rat uterus by 3 times and, as previously shown, did not increase the weight of the prostate and levator ani muscle. The mineralocorticoid activity of gestobutanoyl tablets was studied using peroral administration for 14 d to female rats at doses 100 and 1000 times (2.5 and 25 mg/kg, respectively) the therapeutic dose. Diuresis did not decrease, water was not retained in the rat body, and electrolytes were excreted in the urine and were present in the urine at constant concentrations in all experimental groups, indicating the absence of side mineralocorticoid effects of gestobutanoyl tablets.

Automated summary

Gestobutanoyl, a pregnane steroid, demonstrates glucocorticoid, mineralocorticoid, and antiandrogenic effects in rats, but lacks estrogenic activity.