Histochemical studies of 5-3 -, 20 - and 20 -hydroxysteroid dehydrogenases and possible progestagen production in hamster eggs

S. Niimura, K. Ishida
1976 Reproduction  
Hamster eggs at various developmental stages were studied histochemically for the presence of \g=D\5-3\g=b\-hydroxysteroiddehydrogenase (HSD) (pregnenolone as the substrate and NAD as the cofactor), 20\g=a\-HSD (20\g=a\-hydroxypregn-4-en-3-one and NADP) and 20\g=b\-HSD(20\g=b\-hydroxypregn-4-en-3-one and NAD). All three enzymes were absent from ovarian eggs but were demonstrated in unfertilized and fertilized eggs up to the blastocyst stage. The activities varied only slightly.
doi:10.1530/jrf.0.0480275 pmid:994098 fatcat:a7xioh5tarhvvitit5byym2cym