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B Brown

Publications and source records attributed to B Brown.

At least 361 records · Page 20Linked to original sources

Formation and secretion of 5alpha-androstan-17beta-ol-3-one, 5alpha-androstan-3alpha,17beta-diol and 5alpha-androstan-3beta,17beta-diol by the perfused rabbit testis epididymis.

Rabbit testes epididymides were perfused in vitro at 36.5 C with an artificial medium containing bovine red blooc cells. Three major testosterone metabolites were formed and subsequently elaborated into the venous effluent of testes epididymibdes when testosterone-1,2,6,7-3-H was infused into the artery of the perfused organ. In contrast, testosterone-1,2,6,7-1-H remained unchanged when incubated in the artificial medium under similar conditions. Elution volume from a Sephadex LH-20 column, development in three ascending paper chromatographic (APC) systems, acetylation and development in a fourth APC system followed by gas liquid chromatography (GLC) of the acetylated products tentatively identified the radioactive-metabolites as 5alpha-androstan-17beta-ol-3-one (DHT), 5alpha-androstan-3alpha,17beta-diol (3alphaol) and 5alpha-androstan-3beta,17beta-diol (3beta-ol). The identity of these 5alpha-reduced testosterone metabolites was confirmed by crystallization to constant specific activity in the presence of authentic carrier steroid. These results suggest that DHT and androstanediols formed by perfused rabbit testes epididymides subsequently escape into the venous effluent.

Androstanes↗

Testosterone and 5alpha-reduced androgen secretion by rabbit testes-epididymides perfused in vitro.

Mass spectrometric determinations confirmed that testosterone, 5alpha-androstan-17betaol-3-one, 5alpha-androstan-3alpha, 17beta-diol and 5alpha-androstan-3beta, 17beta-diol were present in venous effluent of in vitro perfused rabbit testes-epididymides. Testosterone, dihydrotestosterone, 3alpha-androstanediol and 3beta-androstanediol were secreted at 3.1 plus or minus 0.9, 0.7 plus or minus 0.2, 0.4 plus or minus 0.1 and 0.6 plus or minus 0.1 mug/h when testes-epididymides were perfused with an artificial medium containing 2.5 ng/ml NIH-LH-S17, ovine. Surprisingly, testosterone constituted only 64% of the total mass of the four androgens secreted. These results probably reflect in vivo androgen secretion since hourly collections of spermatic vein blood from anesthetized rabbits contained 2.7 plus or minus 0.9, 0.8 plus or minus 0.3, 0.15 plus or minus .04 and 0.5 plus or minus 0.2 mug of testosterone, dihydrotestosterone, 3alpha-androstanediol and 3beta-androstanediol, respectively. Once again testosterone constituted only 64% of the total mass of the four androgens.

Androstanes↗