Changes with age in activities of 4-ene-5 alpha-reductase, 17 beta-ol-dehydrogenase and 17-hydroxylase in normal and neonatally grafted mouse testes.
Male and female (WB X C57BL/6)F1 hybrid mice of various ages were used. Two testes from mice at day 0 after birth were grafted under the capsule of the right kidney of male, female and castrated male mice at 80-100 days of age, and the grafted testes in groups of 12-24 were removed 15-120 days after grafting. Normal testes of various ages were also used. Testicular homogenates were incubated with [3H]progesterone or [14C]4-androstene-3,17-dione, and enzyme activities per g tissue were estimated. Activities of 17-hydroxylase and 17 beta-ol-dehydrogenase increased significantly with age in the normal testes and in the grafted testes in the males, females and castrated males; the most conspicuous increases in activities of 17-hydroxylase and 17 beta-ol-dehydrogenase were found, respectively, from 15 days of age to 30 days and from 30 days to 40 days. In contrast, 5 alpha-reductase activity was the highest at 30 days of age, moderately high at 15 and 40 days and very low at 60 and 120 days in the normal testes as well as in all grafted testes examined under various endocrine conditions, though the peak value at 30 days was significantly higher in the normal testes than in the grafted ones. These results seem to indicate that changes with age in 5 alpha-reductase activity relative to other enzyme activities in mouse testes are at least in part an autonomous process related to the period of gonadotropin stimulation or age of the Leydig cells.
D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000378:metabolism*; D000375:Aging; D000735:Androstenedione / Q000378:metabolism; D000818:Animals; D000831:Animals, Newborn; D002250:Carbon Radioisotopes; D002369:Castration; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010088:Oxidoreductases / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism; D013254:Steroid 17-alpha-Hydroxylase / Q000378:metabolism*; D013250:Steroid Hydroxylases / Q000378:metabolism*; D013256:Steroids / Q000096:biosynthesis; D013737:Testis / Q000201:enzymology / Q000254:growth & development* / Q000637:transplantation; D014316:Tritium
D002250:Carbon Radioisotopes; D013256:Steroids; D014316:Tritium; D000735:Androstenedione; D011374:Progesterone; D010088:Oxidoreductases; D015067:17-Hydroxysteroid Dehydrogenases; D013250:Steroid Hydroxylases; D013254:Steroid 17-alpha-Hydroxylase; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase