低密度脂蛋白对人肾小球系膜细胞增殖的影响

EFFCT OF LDL ON HUMAN MESANGIAL CELL PROLIFERATION

用酶法测定了正常人、肾病综合征（ＮＳ）未服用糖皮质激素和服用糖皮质激素治疗患者的血清脂蛋白组分，用体外肾小球细胞培养的方法观察了正常人及ＮＳ患者的低密度脂蛋白（ＬＤＬ）对正常成年人肾小球系膜细胞（ＨＭＣ）增殖的影响。结果表明：（１）ＮＳ患者的ＬＤＬ构成成分发生改变，其对ＨＭＣ的增殖影响与正常人不同，小剂量时促进ＨＭＣ增殖作用较正常人增强，较大剂量时使ＨＭＣ增殖高峰的下降提前出现。（２）糖皮质激素如无治疗ＮＳ的疗效时，不影响ＮＳ患者ＬＤＬ的构成成分和对ＨＭＣ的作用。系膜细胞病变是肾小球疾病的重要病理部位，我们认为脂质代谢异常可能加速肾脏疾病的进展。

yperlipidemia is one of the main features of nephrotic syndrome(NS),which has been reported to be important in the pathogenesis of mesangial cell proliferation. In an attempt to understand if LDL of the NS patients is more nephrotoxic on the development of mesangial cell proliferation, serum lipoprotein com-position of normal controls,patients of NS untreated and treated with steriod drugs were measured, mor-ever,the influence of LDL from each group of patients on the proliferation of human mesangial cell(HMC)were observed.Lipoprotein composition was measured by enzymic metheds. LDL was prepared by ultracentrifugation and used within three weeks. HMC was cuItured and identified by classical methods,mesangial cell prolif-eration was observed by￣3H-TdR incorporation according to the dose of LDL from 2 0～1000μg/ml and time from 24 hours to 72 hours.Our results indicated that:1.Both the NS patients untreated and treated with steriod drugs showed hypercholestolemia and hypertriglyceride,serum low-density lipoprotein cholesterol( LDL-ch)concentra-tion were higher in these patients than in the normal control group but there was no significent difference between NS untreated and treated groups.2. LDL from normal controls or NS patients had biaphasic ef-fect on HMC proliferation, Low concentration stimulated HMC proliferation in concentrationdependent and time-dependent manner,where as high concentration inhibited HMC proliferation. There was no signifi-cent difference on the effect of HMC proliferation between NS untreated and treated groups. 3. HMC 3￣H-TdR incorporation was maximum at LDL 500 μg/ml in normal control,comparing to LDL from NS untreated and treated groups,in other words, in NS patients lower concentration of LDL was needed than nom1al controls to stimulate HMC proliferation.4. The LDL concentration which inhibited HMC prolifer-ation was lower in NS patients than that in normal controls.From these results,it is presumed that LDL from NS patients increase both in LDL-ch proportion and in the nephrotoxic effect of mesangium proliferation which suggests that it is necessary to attach the impor- tance to treat hyperlipidemia in NS patients.