【摘要】 目的:探讨苦参碱对血管紧张素Ⅱ(angiotensin Ⅱ,Ang Ⅱ)诱导的大鼠心肌成纤维细胞(cardiac fibroblasts,CFs)增殖的抑制作用及其机制。方法:差速贴壁法体外培养新生Wistar大鼠的心肌成纤维细胞,随机分为6组:对照组,AngⅡ组,Losartan+AngⅡ组,不同浓度Mat(0.25﹑0.5﹑1.0mmol/L)+AngⅡ组。MTT法检测细胞的增殖;流式细胞仪分析细胞周期并检测CyclinD1、p21的表达;免疫荧光细胞化学染色法检测p27蛋白表达。结果:(1)AngⅡ可显著提高心肌成纤维细胞MTT-OD值,使S期细胞比率增加,G1期细胞比率下降,并降低细胞p27蛋白的表达。而对CyclinD1、p21蛋白表达无影响。AT1受体拮抗剂Losartan可完全阻断AngⅡ的作用。(2)在一定范围内(0.25～1.0mmol/L),Mat能降低AngⅡ诱导的心肌成纤维细胞MTT-OD值,使S期细胞比率下降,G1期细胞比率增加,并提高心肌成纤维细胞中p27﹑p21蛋白水平,且呈浓度依赖性。结论:(1)AngⅡ通过AT1受体促进CFs增殖,机制可能与降低p27蛋白的表达有关。而与CyclinD1、p21无关。(2)在一定范围内,Mat可剂量依赖性地抑制AngⅡ诱导的心肌成纤维细胞增殖,其作用与增强p27﹑p21的蛋白表达有关。更多还原

【Abstract】 Objective To study the influence of matrine(Mat) on the proliferation of cultured neonatal rat cardiac fibroblasts(CFs) induced by AngiotensinⅡ,and to investigate its mechanism.Methods The neonatal rat cardiac fibroblasts were extracted by enzymatic digestion and anchorage velocity-dependent separation method.CFs were divided into six groups:control group,AngⅡgroup,Losartan group,different concentration Mat(0.25﹑0.5﹑1.0 mmol /L)+ AngⅡ group.CFs proliferation was measured by thiazolyl blue(MTT) assay;Cell cyclin distribution and CyclinD1、p21 expression were determined by flow cytometry.The expression of p27 was detected by immunofluorescence staining.Results(1) Compared with the control group,MTT value of CFs was increased in the Ang Ⅱ group.The percentage of CFs in S stage was upregulated and the percentage of cells in G0 /G1 stage was significantly downregulated by AngⅡ.AngⅡdecreased the expression of p27,but it had no effect on the expressions of CyclinD1、p21(both P > 0.05).(2)Compared with Ang Ⅱ group,MTT values of CFs in Mat + Ang Ⅱ treatment groups were decreased.The percentage of S stage cells was downregulated and the percentage of G0 /G1 stage cells was upregulated when they were simultaneously treated with Mat Ang Ⅱ.Furthermore,coinstantaneous treatment of CFs with Mat and Ang Ⅱ was associated with elevation of p27 and p21.Conclusions(1)Ang Ⅱ-stimulated CFs proliferation was mediated by activation of AT1 receptors.A corresponding decrease in the expression of p27 in CFs may be related to this proliferating effect,which has no correlation with the expression of CyclinD1、p21.(2)Mat could effectively inhibit the Ang II-induced proliferation of CFs by upregulating p27 and p21 expressions in a concentration dependent manner,which may play an important role in the regression of heart remodeling.更多还原