目的：探讨血管紧张素Ⅱ（AngⅡ）对肝星状细胞（HSC）合成胶原的影响及其机制。方法：以不同浓度的AngⅡ刺激大鼠HSC，采用[3H]－脯氨酸（3H-pro）掺入释放法检测胶原合成的情况， RT-PCR检测Ⅰ、Ⅲ型前胶原mRNA的表达，原位杂交及免疫组化的方法分别检测血小板源性生长因子β受体（PDGFR-β）的表达。结果：10－8～10－5 mol／L AngⅡ能剂量依赖性促进HSC对3H-pro的掺入率（P＜0．05），促进胶原的合成，但10－6 mol／L AngⅡ作用最强。与培养激活的大鼠HSC相比，加入10－6 mol／L AngⅡ刺激后，Ⅰ、Ⅲ型前胶原mRNA的表达明显增加。免疫组化结果显示，培养激活的大鼠HSC可表达少量的PDGFR-β蛋白，但与正常对照组相比10－6 mol／L AngⅡ刺激后表达明显增强（P ＜0．01）。细胞原位杂交结果显示10－6 mol／L AngⅡ刺激HSC后表达 PDGFR-β mRNA明显增加（P ＜0．01）。结论：AngⅡ可促进 HSC 胶原的合成， PDGF 信号通路可能在其中起着重要的作用。%Objective To investigate the effect and mechanism of AngⅡ on collagen in hepatic stellate cell. Methods HSCs were isolated and cultured, 3H-pro incorporation method was used to evaluate the effects of different doses of AngⅡ on the proline syntheses. RT-PCR assay were used to assess changes in mRNA expression levels of type Ⅰ and Ⅲ procollagen. PDGFR-β mRNA and protein were determined by in situ hybridization and immunocytochemistry. Results 10-8~ 10-5 mol/L AngⅡ could significantly increase the 3H-pro incorporation rate of HSC in a dose-dependent style, 10-6 mol/L AngⅡis the most effective dose. The cultured HSC showed a little expression of type Ⅰ and Ⅲ procollagen mRNAs, while 10-6 mol/L AngⅡwas able to enhance the expression for type Ⅰ and Ⅲ procollagen mRNAs significantly(P < 0.01). AngⅡalso could enhance both mRNA and protein expression of PDGFR-β on HSC(P < 0.01). Conclusion These results suggest that AngⅡ could promote HSC collagen synthesis by enhancing the expressions of PDGFR-β.
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