Oxidoreductase with a preference for NAD. Oxidizes all-trans-retinol and 13-cis-retinol to the corresponding aldehydes. Has higher activity towards CRBP-bound retinol than with free retinol. Oxidizes 3-alpha-hydroxysteroids. Oxidizes androstanediol and androsterone to dihydrotestosterone and androstanedione. Can also catalyze the reverse reaction.
Highly expressed in adult liver (at protein level). Detected in endometrium, liver and foreskin. Detected in the spineous layers of adult skin, and at lower levels in basal and granular skin layers. Detected in fetal liver and lung.
Belongs to the short-chain dehydrogenases/reductases (SDR) family.