Hormonal regulation of male-specific 20beta-hydroxysteroid dehydrogenase with carbonyl reductase-like activity present in kidney microsomes of rats.
Progesterone, 17alpha-hydroxyprogesterone, cortisone and cortisol, which are C(21)-steroids with a ketone group at the 20-position, potently inhibited the activity of enzyme acetohexamide reductase (AHR) responsible for the reductive metabolism of acetohexamide in kidney microsomes of male rats. Furthermore, progesterone was a competitive inhibitor of AHR. In the case of progesterone usage as the substrate, 20beta-hydroxysteroid dehydrogenase (20beta-HSD) activity was much higher than 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) activity in kidney microsomes of male rats. These results indicate that AHR present in kidney microsomes of male rats, functions as 20beta-HSD with carbonyl reductase-like activity. In male rats, both testectomy and hypophysectomy decreased the renal microsomal 20beta-HSD activity, but the decreased enzyme activities were increased by the treatment with testosterone propionate (TP). We propose the possibility that TP treatment regulates the renal microsomal 20beta-HSD activity by acting directly on the kidney of male rats. This is supported from the fact that when TP was given to ovariectomized and hypophysectomized female rats, the male-specific 20beta-HSD activity was detected in their kidney microsomes.
Imamura
Y
Y
Faculty of Pharmaceutical Sciences, Kumamoto University, 5-1, Oe-honmachi, 862-0973, Kumamoto, Japan. yorishig@gpo.kumamoto-u.ac.jp
Takada
H
H
Kamizono
R
R
Otagiri
M
M
D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000818:Animals; D003349:Cortisone Reductase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005260:Female; D007668:Kidney / Q000201:enzymology*; D008297:Male; D008861:Microsomes / Q000201:enzymology*; D009919:Orchiectomy; D010902:Pituitary Gland / Q000601:surgery; D051381:Rats; D011916:Rats, Inbred F344; D012737:Sex Factors; D013379:Substrate Specificity
D000429:Alcohol Oxidoreductases; D003349:Cortisone Reductase