Localization of Δ4-5α-Reductase in Immature Rat Testes*

Autor:	Keishi Matsumoto, Leo T. Samuels, Kenichi Yoshizaki
Rok vydání:	1978
Předmět:	chemistry.chemical_classification medicine.medical_specialty G protein Biology Endocrinology Seminiferous tubule medicine.anatomical_structure Enzyme chemistry Internal medicine medicine Collagenase Pregnenolone Microsome Incubation Testosterone medicine.drug
Zdroj:	Endocrinology. 102:918-925
ISSN:	1945-7170 0013-7227
DOI:	10.1210/endo-102-3-918
Popis:	Testes of 29–35-day-old rats were separated into seminiferous tubules and interstitial tissue by collagenase treatment and examined by incubation studies with radioactive substrates. The activity of testosterone 5α-reductase/g protein in the interstitial tissue was 37 times greater than that in the tubules. The site of formation of 5α-reduced C21- and C19-steroids from progesterone was found to be primarily in the interstitial tissue. In the interstitial tissue, testosterone 5α-reductase activity, which was stimulated 300-fold by the addition of NADPH, was localized in the microsomal fraction (8,000–105,000 × g precipitate). NADPH was five times as effective a hydrogen donor as NADH when the washed microsomal fraction was the source of the enzyme. The formation of 5α-reduced C21- and C19-steroids from pregnenolone and progesterone was demonstrated in the microsomal fraction of interstitial tissue. These results indicate that in 29–35-day-old rat testes, 5α-reduction of C19-Δ4-3-ketosteroids and the format...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::7220518b657e7046ec03558610c38894 https://doi.org/10.1210/endo-102-3-918 Zobrazit plný text záznamu