Serum lipid and lipoprotein patterns of subjects with/without coronary sclerosis and having less than 300 mg/100 ml of serum total cholesterol were analyzed. Subjects woth coronary sclerosis were classified into 2 groups, myocardial infarction (MI) group and coronary sclerosis (CS) group, in accordance with the criteria for the diagnosis of coronary sclerosis established by the special study group of the Educational Ministry in 1960. 2. While serum total cholesterol was higher in the MI group than in the other groups, there was no difference in total cholesterol concentration between the CS group and the control. However, the concentration of free cholesterol, triglycerides, total phospholipids and total lipids increased in the control, the CS and the MI group in this order. 3. The percent concentration of pre-beta and beta and the ratio of beta/alpha and pre-beta+beta/alpha increased in the control, the CS and the MI group in this order. Type IIb hyperlipoproteinemia was observed more frequently in the MI group than in the control one. Type IIa and IV hyperlipoproteinemia did not change into any other phenotypes, but Type IIb changed occationally into Type IIa. 4. So called extra pre-beta lipoprotein was observed more frequently in the CS and MI groups than in the control one. 5. These results suggested that even slight changes in serum lipid and lipoprotein patterns might be related to atherogenecity.
