In addition to the acid and neutral sphingomyelinases (SMase) that occur in most tissues,
distinct alkaline sphingomyelinases occur in the mucosa of the gastrointestinal tract and
human bile. These enzymes exhibit characteristic properties with regard to bile-salt
dependence, protease resistance, and longitudinal distribution in the gut. Alkaline SMase
has now been partially purified from human bile and from rat small intestine. It is thought to
have a role in sphingomyelin (SM) digestion but may also be important for the generation of …