Influence of liver injury on testosterone 5 alpha-reductase activity in the rat diencephalon.

Diencephalon testosterone 5 alpha-reductase activity and plasma testosterone level were measured in the rat with liver injury caused by i.p. administration of CCl4. Testosterone levels in plasma were decreased after CCl4 injection in both group I (0.1ml/150g B.W./once a day for 2 days) and group II (0.01ml/150g B.W./twice a week for three weeks). 5 alpha-Reductase activity in the diencephalon was decreased both on the 7th day after administration in group I and in group II, while being transiently increased on the 1st day after administration in group I. These results suggest that testosterone metabolism in the brain is inhibited during liver disorders.