血管紧张素-（1-7）对TGF-β1诱导大鼠心肌成纤维细胞增殖和胶原合成的影响

目的：观察血管紧张素-（1-7）对TGF-β1诱导幼年大鼠心肌成纤维细胞增殖（CF）和胶原合成的影响,并探讨其是否通过cAMP/PKA通路进行介导抗纤维化作用。方法：①细胞分离培养与鉴定：用酶消化法分离细胞,差速贴壁法纯化获得心室肌成纤维细胞为材料,用光学显微镜和免疫细胞化学的方法鉴定细胞。②检测方法：WST-1比色法测定细胞增殖情况,放射免疫法测定Ⅲ型胶原前胶原末端肽（PCⅢ）的含量。结果：①与空白组比较,Ang-（1-7）组呈浓度依耐性抑制基础状态下CF和PCⅢ分泌（P〈0.05）;②在TGF-β1诱导状态下,与TGF-β1组比较,Ang-（1-7）＋TGF-β1组呈浓度依耐性抑制FBC增殖和PCⅢ分泌（P〈0.05）;③与Ang-（1-7）比较,Ang-（1-7）＋H-89组基础状态下抑制CF增殖和PCⅢ分泌能力减弱（P〈0.05）;④在TGF-β1诱导状态下,H-89（PKA抑制剂）能阻断Ang-（1-7）对CF的增殖和胶原合成的抑制作用。结论：1.Ang-（1-7）对基础状态下或TGF-β1诱导下CF增殖和胶原合成均具有明显抑制作用,且呈浓度依赖性。②Ang-（1-7）是通过PKA介导抑制TGF-β1诱导CF增殖及胶原合成。

EFFECT OF ANG-(1-7)ON THE PROLIFERATION AND SYNTHESIS OF COLLAGEN IN CULTURED RAT CARDIAC FIBROBLAST INDUCED BY TGF-B1

Objective：To observe the effect of Ang-（1-7） on the proliferation and synthesis of collagen in cultured rat cardiac fibroblast induced by TGF-β1,and to evaluate whether its intracellular signaling pathway is mediated by cAMP/PKA.Methods： Cardiac fibroblast was isolated by enzyme digestion and differential attach-ment method,and identified by light microscope and immuocytochemistry.The influence of Ang-（1-7） on cardiac myofibroblasts proliferation was determined by WST-1 assay.The protein content of PCⅢwas determined by ra-dioimmunoassay.Results：①Compared with the control group,Ang-（1-7） inhibited the proliferation and synthesis of collagen in cardiac myofibroblasts in the basic state.②Ang-（1-7） inhibited the proliferation and synthesis of PC Ⅲin cardiac myofibroblasts induced by TGF-β1.③Compared with Ang-（1-7） group,the ability of inhibiting the proliferation and synthesis of PCⅢin Ang-（1-7）＋H-89 group decreased in the basic state.④H-89 attenuated the extent of inhibiting the proliferation and synthesis of collagen in cardiac myofibroblasts caused by Ang-（1-7） in the state of induced-TGF-β1.Conclusions： ①Ang-（1-7） can not only inhibit the proliferation and synthesis of collagen in cardiac myofibroblasts in the basic or TGF-β1-reducing state with a concentration-dependent man-ner.②The PKA pathway is likely involved in the proliferation and synthesis of collagen in cardiac myofibroblasts induced by TGF-β1.