ANDROGENS AND RELATED COMPOUNDS IN THE SPERMATIC VEIN BLOOD OF DOMESTIC ANIMALS

Abstract

SUMMARY Ox and sheep blood is able to reduce androstene-3:17-dione in the presence of oxygen to form 17α-hydroxyandrost-4-ene-3-one (epitestosterone), accompanied by lesser amounts of testosterone. The blood of these two ruminant species differs in this respect from that of the pig, the stallion and man, which on aerobic incubation with androstenedione produces small amounts of testosterone, but none of the 17α-epimer. The neutral steroid 17α-ol dehydrogenase activity in ruminant blood is independent of the sex of the animal, and resides in the cellular fraction of the blood. The action of the enzyme in ox blood was shown to be reversible, but in whole blood the oxidative step proceeds at a very slow rate. The reported occurrence of epitestosterone in spermatic vein blood of young calves is attributed to the action of the blood on androstenedione released by the testis.