Cholesterol turnover and risk factors for the development of coronary heart disease.
Lecithin cholesterol acyltransferase (LCAT) appears to be one of the factors controlling the intravascular turnover rate of cholesterol. LCAT activity in healthy subjects is significantly higher in men than in women of the same relative body weight, total and free cholesterol and triglycerides. In healthy men sleep deprivation induced a decrease in LCAT activity combined with a decline of serum cholesterol concentration; consequently, the intravascular turnover rate of cholesterol did not significantly change. In hypertensive patients the decrease in cholesterol turnover rate correlated with the degree of hypertension and the response of blood pressure to medication. Reduced turnover rate of cholesterol was more frequent in men than in women, in spite of higher plasma cholesterol concentration in the latter. During a 4-month period of treatment etiroxate of hyperlipoproteinemia II and IV, the only significant change in plasma cholesterol level was a drop observed after the first two weeks; on the other hand, the turnover rate of cholesterol rose gradually and approached normal values due to a highly increased LCAT activity. Obesity and diabetes were associated with a high percentage of deviations in the studied parameters of cholesterol metabolism. The turnover rate of cholesterol measured three months after acute myocardial infarction was below normal in 80% of patients, whereas hypercholesterolemia was manifested in only less than 40%. The results imply that the intravascular turnover rate of cholesterol estimated by measurement of LCAT activity may be a suitable indicator of the internal balance of cholesterol, substantially more delicate and discriminative than a mere determination of the actual plasma concentration of cholesterol or plasma lipoprotein. Judging by our observations, deviations in the internal dynamics of cholesterol may play an important role in the pathogenesis of coronary atherosclerosis.
D002784:Cholesterol / Q000097:blood*; D003327:Coronary Disease / Q000175:diagnosis*; D003920:Diabetes Mellitus / Q000097:blood / Q000201:enzymology; D004951:Esterification; D005260:Female; D006801:Humans; D006973:Hypertension / Q000097:blood / Q000201:enzymology; D008297:Male; D009765:Obesity / Q000097:blood / Q000201:enzymology; D007862:Phosphatidylcholine-Sterol O-Acyltransferase / Q000097:blood*; D012306:Risk
D002784:Cholesterol; D007862:Phosphatidylcholine-Sterol O-Acyltransferase