title: Maturational changes in steroidogenic enzyme activities metabolizing testosterone and dihydrotestosterone in two populations of testicular interstitial cells.
abstract: The present study examined changes in steroidogenic enzyme activities which metabolize testosterone or dihydrotestosterone between days 21-73 of maturation in Band 2 and Band 3 cells isolated by centrifugation of rat testicular interstitial cells on metrizamide density gradients. 5 alpha-reductase and 17 beta-hydroxysteroid dehydrogenase activities increased progressively in Band 2 and Band 3 cells between days 21-35 of maturation, then both enzyme activities declined to reach low levels in adult Band 2 and Band 3 cells. The significantly higher activities of both enzymes in Band 3, which contains a greater concentration of Leydig cells at each age, suggest their localization in Leydig cells. 5 alpha-androstane-3 alpha- and 3 beta-hydroxysteroid dehydrogenase activities increased in both Band 2 and Band 3 cells between days 21-50 of maturation and remained elevated; however, dihydrotestosterone was metabolized primarily to 5 alpha-androstane-3 beta,17 beta-diol in Band 2 cells, while 5 alpha-androstane-3 beta,17 beta-diol was the major metabolite of dihydrotestosterone in Band 3 cells. These studies suggest that testosterone accumulation during sexual maturation can be influenced by changing patterns of 5 alpha-reductase and 17 beta-hydroxysteroid dehydrogenase activities which metabolize testosterone, and of 5 alpha-androstane-3 alpha- and 3 beta-hydroxysteroid dehydrogenase activities which metabolize dihydrotestosterone in both Band 2 and Band 3 cells.
authors.affiliation: Medical Research Service, WJB Dorn Veterans' Hospital, Columbia, South Carolina.
authors.forename: E P
authors.initials: EP
authors.lastname: Murono
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000378:metabolism; D000818:Animals; D002469:Cell Separation; D002470:Cell Survival; D013196:Dihydrotestosterone / Q000378:metabolism*; D006651:Histocytochemistry; D007985:Leydig Cells / Q000378:metabolism*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D012741:Sexual Maturation; D013739:Testosterone / Q000378:metabolism*
chemical_list: D013196:Dihydrotestosterone; D013739:Testosterone; D015067:17-Hydroxysteroid Dehydrogenases; D015096:3-Hydroxysteroid Dehydrogenases; C032690:3-alpha-(17-beta)-hydroxysteroid dehydrogenase (NAD(+)); D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase