Steroid secretion by in vitro perfused testes: secretions of rabbit and rat testes.

Publisher Website
Google Scholar
Abstract
Steroids, which are testosterone [T] biosynthetic intermediates, were identified as testicular secretions in several species. The identification of these steroids in the venous effluent of testes perfused in vitro would suggest the presence of T biosynthetic pathways. GLC and mass spectrometry were utilized to identify and quantitatively measure 11 steroids secreted by rat and rabbit testes perfused in vitro. The steroid secretion rates (.mu.g/h per testis) for the rat (n = 20) and rabbit (n = 29), respectively, were: pregnenolone (2.7 .+-. 0.3, 0.2 .+-. 0.03) (.hivin.x [mean] .+-. SE); 17.alpha.-hydroxypregnenolone (2.6 .+-. 0.3, 1.2 .+-. 0.1); dehydroepiandrosterone (0.2 .+-. 0.02, 1.3 .+-. 0.1); androstenediol [DIOL] (nondetectable, 1.7 .+-. 0.3); progesterone (0.4 .+-. 0.05, 0.08 .+-. 0.03); 17.alpha.-hydroxyprogesterone (0.8 .+-. 0.08, 0.9 .+-. 0.1); androstenedione (0.1 .+-. 0.01, 0.4 .+-. 0.04); T (3.3 .+-. 0.2, 13.2 .+-. 0.9); dihydrotestosterone (0.01 .+-. 0.006, 4.2 .+-. 0.3); 3.beta.-DIOL (0.01 .+-. 0.007, 0.8 .+-. 0.1); 3.alpha.-DIOL (0.01 .+-. 0.007, 0.34 .+-. 0.07). In contrast to the rabbit, DIOL was not secreted by rat testes. Only trace amounts of dihydrotestosterone, 3.alpha.-DIOL, and 3.beta.-DIOL were found in the venous effluent of rat testes. Although T was the predominant steroid secreted by rabbit testes, pregnenolone and T secretion rates were similar for rat testes. More than 1 biosynthetic pathway may contribute to the formation of T in rat and rabbit testes.