THE METABOLISM OF INJECTED ³H-TESTOSTERONE IN THORACIC DUCT LYMPH OF MALE RATS

Abstract

Ten μc of [1, 2-³H] testosterone was injected intravenously, as a single dose, to male intact, castrated, adrenalectomized and hypophyse-tomized rats. The lymph from thoracic duct was collected continuously at varing intervals for 160min after the injection. In all animal groups the intravenously injected hormone appeared in the lymph, with maximum radio-activity in the first five minute lymph specimen, and disappeared afterward at a very rapid rate. The pattern of appearance of radioactivity in the lymph was similar to that in blood circulation. A greater proportion of raioactivity appeared in the early 40minute lymph specimen. The values of cumulative radioactivity were higher in the lymph of both adrenalectomized and hypophysectomized animal groups than those of both intact and castrated ones. It was mentioned that the hypophyseo-adrenal axis might be responsible for this phenomenon. The estimated biological half-lives in the lymph were longer in castrated animals than those in the other groups. A possible reason for this was discussed.