抄録
The role of serum carboxyl esterase in cholesterol ester hydrolysis in atheromatous lesions was investigated. Purified serum carboxyl esterase hydrolyzed cholesterol oleate emulsified with lecithine from pH 4.5 to pH 8.0. In human atheromatous lesion, carboxyl esterase activity was observed, and an immuno-reactive substance with carboxyl esterase was also found in thick intima portion by immunofluolescent study using monoclonal antibodies. [3H]Cholesterol oleate in lipid droplet formed in rat peritoneal macrophages was also hydrolyzed with carboxyl esterase. Addition of carboxyl esterase to macrophages loaded with acetylated LDL-[3H]cholesterol linoleate, increased the release of [3H]cholesterol. These results suggests that carboxyl esterase might promote the hydrolysis of cholesterol ester in atheromatous lesion.