Sorbitol dehydrogenase, also known as L-iditol 2-dehydrogenase and SORD, is a member of the zinc-containing alcohol dehydrogenase family. SORD exsits in a homotetramer and binds one zinc ion per subunit. SORD is expressed in kidney and epithelial cells of both benign and malignant prostate tissue. SORD can converts sorbitol to fructose and catalyzes the interconversion of polyols and their corresponding ketoses, and together with aldose reductase to make up the sorbitol pathway. SORD is up-regulated by androgens and down-regulated by castration. SORD may play a role in the sperm motility by providing an energetic source for sperm.