EVIDENCE FOR EARLY TESTIS HORMONE SECRETION IN THE RAT FROM A STUDY OF THE EPIDIDYMIS1

Abstract

Wt. change in the epididymis of castrated and controls litter-mate [male] rats was used as an indicator of testis hormone secretion. Twenty-eight pairs of rats (with 7 additional animals) operated on day one were autopsied from day 6 to 45. Divided into 2 age groups (day 6-20, 21-45) the castrates in the younger group showed an avg. decline of 21% below that of their controls and in the older group, 50%. Inj. of small amts. of testosterone propionate (0.01 mg) daily, from day 3 to autopsy on days 8 to 13 into day one castrates of 15 pairs resulted in detectable increases in wt. of the epididymis. Hormone secretion in normal rats can be detected by wt. changes in the epididymis on the 8th postnatal day.