Conversion of progesterone-1,2-3-H to 5beta-pregnane-3,20-dione by brain tissue.
The presence of a 5beta-reductase acting to convert progesterone to 5beta-pregnane-3,20-dione is described in the soluble 105,000 x g fraction of a preparation of dog cerebral cortex. The function of this enzymatic activity is obscure but may be important in regulation of sensorium. 5beta-pregnane compounds are potent depressors of the central nervous system.
D000818:Animals; D002540:Cerebral Cortex / Q000201:enzymology*; D003460:Crystallization; D004285:Dogs; D006913:Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D011277:Pregnanediones / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism*; D011375:Progesterone Reductase / Q000378:metabolism*; D014316:Tritium
D011277:Pregnanediones; D014316:Tritium; D011374:Progesterone; D006913:Hydroxysteroid Dehydrogenases; D011375:Progesterone Reductase