Reaction catalyzed by 3(or 17)alpha-hydroxysteroid dehydrogenase (1.1.1.209)
+
NADPH
+
=
+
NADP+
5alpha-androstan-3alpha-ol-17-one
+
NADPH
+
H+
=
5alpha-androstan-3alpha-ol-17beta-ol
+
NADP+
