[New approach from lipoprotein disorders to atherosclerosis]

To make diagnosis arteriosclerosis directly by biochemical markers is not easy, but to identify risk factors by biochemical markers is useful. Lipoprotein disorder is one such risk factor. Low density lipoproteins (LDL), remnants and small LDL were high risks of coronary disease in Japanese. Moreover, those incidences were significantly higher in diabetes mellitus, especially with nephropathy, and latter two lipoproteins frequently coexisted. Oxidizability of small LDL was the highest among LDLs, indicating that small LDL promotes atherosclerosis by forming oxidized lipids, which enhance complicated lesion of atherosclerosis. The mechanism by which the remnant is retained remains unknown. We measured LPL mass in preheparin serum. Preheparin LPL mass was negatively correlated with triglyceride, and positively correlated with high density lipoprotein cholesterol. Further more, preheparin LPL mass was lower in remnant-positive persons, indicating that preheparin LPL mass might be involved in remnant clearance. Understanding the role and catabolism of LPL itself requires further study.