ABSTRACT
Acyl-CoA:cholesterol O-acyltransferase is the intracellular cholesterol esterifying enzyme. It has two isoenzymes, ACAT1 and ACAT2. In humans, ACAT1 is distributed widely, whereas ACAT2 is confined to the apical region of the intestinal villi. In the gut, free cholesterol absorbed as a product of digestion and newly synthesized cholesterol are esterified by ACAT2 before secretion in chylomicrons. Inhibitors of ACAT (e.g. synthetic fatty acids capable of binding to the enzyme but not of being esterified to cholesterol) have attracted interest, because of their potential as hypocholesterolaemic drugs.
