In vitro Activation of Lipolytic Activity in the Serum of Dogs by Bile Salts. ∗

Summary

The inactive precursor of a lipolytic enzyme which requires bile salts for activation in vitro has been identified in serum from dogs and cats, and bile from dogs. It is absent from the serum of humans, rabbits, rats and goats. The activated enzyme has been referred to as cholate activated lipase(CAL). Both CAL and its inactive precursor are heat labile. The pH optimum of CAL is 8.0-8.3. CAL rapidly hydrolyzes long and short chain fatty acid triglyceride. Eserine and hexestrol are inhibitors of CAL. Comparison of the effect of various potential inhibitors on CAL with their effects on pancreatic lipase and postheparin lipase suggest that the lipolytic enzymes from these three sources are not identical.