Comparative Biochemical Studies on Plasma Cholesterol—I Activity of Carp Plasma Lecithin: Cholesterol Acyltransferase

Abstract

Although there is quite a few data available on the esterification of cholesterol in land animals, almost no research is available on fishes. In the present paper, the plasma lecithin:cholesterol acyltransferase (LCAT) activities of carp, Cyprinus carpio, were measured under the normal, starved, and diabetic conditions. Its optimum pH was around 6.5-7.0 and the maximum activity was obtained at 37'C in the experimental condition. The LCAT activity of starved carp was about 50% higher than that of the control. In the diabetic case, the LCAT activity increased approximately 80%. Generally, the LCAT activity as well as the proportion of cholesterol esters in the plasma of carp are less than those of man, suggesting somewhat different structure of lipoproteins which transport free and esterified cholesterols with other lipid components. © 1979, The Japanese Society of Fisheries Science. All rights reserved.