The effect of 17 β -estradiol acetate on the testis and thumb pad of Rana cyanophlyctis (Schn.) and Rana tigrina (Daud.)

The effect of 17 β -estradiol acetate on the testis of two frogs Rana cyanophlyctis and Rana tigrina has been studied. 17 β -estradiol administration has an inhibitory action on spermatogenesis and also on Leydig cell secretory activity. There is a marked reduction in the Δ5-3 β -hydroxysteroid dehydrogenase (Δ5-3 β -HSDH) and glucose-6-phosphate dehydrogenase (G-6-PDH) activities in the Leydig cells accompanied by a marked rise in the free and the total cholesterol content of the testis. This suggests a reduction in androgen synthesis which is reflected in the regression of the androgen-dependent secondary sexual characters, the thumb pads