Oleylglycerol hydrolysis and acyl-CoA-independent transacylation with cholesterol by enzyme preparations from pig aorta.

We demonstrated preferential hydrolysis of trioleylglycerol greater than 1.3-dioleylglycerol greater than 1-monooleylglycerol expressed as acyl equivalents of glycerol rather than fatty acid released by pig aortic lipase. Transacylation with cholesterol occurred in the reverse order of the substrates in an appropriate reaction system.

Effect of substrate composition and concentration on aortic cholesterol ester hydrolase activity.

Cholesterol ester hydrolase activity of pig aorta has been examined under optimum experimental conditions for hydrolysis of different cholesterol esters. The enzyme specific activity values were in the numerical order of substrates hydrolyzed: cholesteryl linoleate larger than or equal to linolenate greater than palmitate larger than or equal to stearate greater than oleate. The results are discussed in relation to the arterial accumulation of cholesterol esters.