長期血液透析患者における血中脂質の変動

―ことに高脂血症改善剤および脂肪乳剤投与の影響について(第3報)

抄録

Artron and clofibrate, which are effective in lowering plasma lipids, and intralipid, which is have an effect of fat load, were administrated to 15 patients undergoing maintenance hemodialysis with 3 months intervals of each drug and plasma lipids, PHLA and IRI were examined. 1) Those parients were stable biochemically by 18-24 hours hemodialysis a week and showed hypertriglyceridemia, increased free fatty acids (FFA), hypocholesterolemia, low level of PHLA and hyperinsulinemia before commencing medications. This kind of hyperlipidemia (high triglyceride, high FFA and low cholesterol) does not belong to the classification of Fredrickson. 2) The administration of artron (3 tablets daily for 56 days) resulted in a statistically significa-nt reduction of total cholesterol. IRI was also elevated by this drug. However, other plasma lipid fractions (β-lipoprotein, phospholipid, FFA) and PHLA were not altered. 3) The administration of clofibrate (750 mg daily for 28 days) resulted in a statistically signifi-cant reductions in total cholesterol, triglyceride and β-lipoprotein. However, there were no effects on phospholipid, FFA, PHLA and IRI. 4) By the fat load (500 ml of intralipid intravenously), total cholesterol, triglyceride and FFA were elevated to statistically significant levels after 8 hours with continuously high levels after 21 hours. Phospholipid, β-lipoprotein and IRI were not altered. It is in interest that PHLA was elev-ated to a statistically significant level after 8 hours and showed a still high level after 21 hours. If intralipid was loaded on the day of hemodialysis, total cholesterol, triglyceride and FFA also incre-ased to a statistically significant levels with lesser extent. 5) From this study, pathogenesis of hyperlipidemia, especially of triglyceride and FFA, was not completely elucidated. PHLA was continously low through the course of chronic hemodialysis and was not altered by drugs which lowered plasma level of triglyceride. It is in interest that the exog-enous elevation of plasma levels of triglyceride and FFA associated the elevation of PHLA. It is assumed that there are several factors which produce abnormalities of lipid metabolism in patients with intermittent hemodialysis. (I) High level of plasma insulin does not facilitate triglyceride synthesis in liver in one to one fashion, but hyperinsulinemia favors this pathway through the longterm hemodialysis. (II) High chlorie diet among patients with chronic hemodialysis resulted in increased utilization of FFA as a calorie source. Metabolic rate of FFA increases in association with increased FFA synthesis, and resynthesis of triglyceride from FFA will probably occur. (III) The possible synthesis mechanism of new acids and there after glycerides, from the exce-ssive amount of glucose and acetate absorbed through the dialysis membrane, should be considered. (IV) Large dosis of heparin is used generally at every hemodialysis and hemodialysis patient may obtain the low responsiveness to exogenous heparin. This leads to low PHLA and delayed clearing of triglyceride from blood.