摘要：目的观察不同浓度低密度脂蛋白(LDL)及氧化修饰低密度脂蛋白(ox-LDL)对人系膜细胞(HMC)增殖和细胞毒性作用，及对培养细胞上清Ⅳ型胶原的含量及表达Ⅳ型胶原α₁链mRNA的影响。方法采用体外HMC培养，H₃-thymidine掺入研究人系膜细胞增殖，LDL释放实验研究细胞毒作用，ELISA法测定Ⅳ型胶原含量和逆转录-聚合酶链反应(RT-PCR)法研究Ⅳ型胶原α₁链mRNA表达。结果LDL能刺激HMC增殖；低浓度ox-LDL抑制HMC增殖，高浓度ox-LDL剂量依赖性表现细胞毒性作用；LDL和低浓度ox-LDL能通过上调HMC表达Ⅳ型胶原α₁链mRNA促进其产生Ⅳ型胶原。结论LDL在引起和促进肾小球硬化的发生和发展中起一定作用，LDL氧化后，可加重该作用。

Effects of LDL and ox-LDL on human mesangial cells proliferation and mesangial matrix production

TAO Jianling ,LI Xuewang ,SU Ying,et al.

(Department of Nephrology,Peking Union Medical College Hospital,Beijing 100730,China)

Abstract：Objective To observe the effects of LDL and ox-LDL on human mesangial cells(HMC)proliferation and viability,the concentrations of collagen Ⅳ in the supernatants of cultured HMC and the expression of collagen Ⅳα₁ mRNA by HMC.Methods The culture of HMC was established in vitro.Cell proliferation and viability were studied by H₃-thymidine incorporation and LDH releasing test respectively.The concentration of collagen Ⅳ was measured by ELISA and the expression of collagen Ⅳα₁ mRNA was examined by RT-PCR.Results HMC proliferation could be stimulated by LDL and be inhibited by ox-LDL at low concentrations.Cytotoxicity was showed by ox-LDL at high concentrations in concentration-dependent manner.Production of collagen Ⅳ by HMC could be stimulated by either LDL or ox-LDL at low concentrations via promoting HMC expression of collagen Ⅳα₁ mRNA.Conclusion LDL and ox-LDL may contribute to the pathogenesis of glomerulosclerosis through influencing the mesangial cell proliferation or viability and accumulation of mesangial matrix.

Keywords：Low density lipoprotein;Collagen type Ⅳ;Glomerulosclerosis;Oxidized low density lipoprotein;Mesangial cell;参考文献：

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收稿日期：1998-12-24