日本人の血漿リポ蛋白濃度に関する研究

Abstract

It has been reported that the incidence of ischemic heart disease in Japan is much lower than that in Western countries. Contribution of genetic or environmental factors to this difference has not been established. The close association between premature atherosclerosis and increased concentrations of low density lipoprotein (LDL) or decreased concentrations of high density lipoprotein (HDL) has been indicated. By means of sequential ultracentrifugation of plasma from Japanese 15 maternal infant pairs, very low density lipoprotein (VLDL d<1.006g/ml), LDL (1.006<d<1.063g/ml) and HDL (d<1.063g/ml) were obtained and analysed for cholesterol (Ch), triglyceride (TG), phospholipid (PL) and apolipoprotein B (Apo B). These results were compared to values in Western countries reported in the literature.Umbilical cord (U) plasma-Ch, TG, PL and Apo B were 73±16, 51±10, 110±21 and 48±16 (mean±S.D.) mg/100ml, respectively. In cord blood, the concentrations of Ch, TG and PL in all lipoprotein density classes were less than one half of those in normal adults or mothers and HDL, was the predominant Ch, TG and PL carrying lipoprotein. Cord blood have higher levels of HDL-Ch and lower levels of LDL-Ch than normal adults. Therefore, HDL-Ch/LDL-Ch ratio in cord blood (1.58±0.32) was higher than the ratio in normal adults (0.50±0.11) and cord blood had relatively more antiatherogenic lipoprotein than adults.Japanese cord blood contained higher levels of HDL-Ch and lower levels of LDL-Ch than those in Sweden, U.S.A. and Australia. HDL-Ch/LDL-Ch ratio were 1.58 in Japan, 1.14 in U.S.A., 0.89 in Australia and 0.69 in G.D.R. HDL-Ch/LDL-Ch ratio in Japanese cord blood was the highest in the values reported in the literature.The relationships between maternal and infant lipoproteins were more significant in HDL than in VLDL or LDL. The positive correlation between maternal HDL and infant HDL may indicate the possibility of placental transfer of intact HDL particle.