马齿苋总黄酮对血小板源性生长因子致家兔血管平滑肌细胞增殖的抑制作用

目的: 研究马齿苋总黄酮(Portulaca total flavone,PTF)对血小板源性生长因子-BB型(PDGF-BB)致血管平滑肌细胞(Vascular smoothmuscle cell,VSMC)增殖的影响并探讨其机制。方法: 采用组织贴壁法培养家兔胸主动脉血管平滑肌细胞,细胞计数法观察PTF(8、24、72 mg/L)对PDGF-BB所致的VSMC增殖作用的影响;氚-胸腺嘧啶核苷(3H-TdR)掺入方法测定VSMC DNA的合成;流式细胞仪分析增殖细胞周期,荧光分光光度计测定VSMC内 Ca²⁺]_i。结果: PTF以浓度依赖方式抑制PDGF-BB诱导的VSMC增殖、DNA合成,血管平滑肌细胞处于G₁/G₀ 期的细胞数增多,而G₂/S期的细胞数显著减少(P<0.01);能抑制高K⁺诱导的VSMC内Ca²⁺]_i升高(P<0.01)。结论: PTF可明显抑制PDGF-BB诱导的VSMC增殖,其作用机制可能与其降低VSMC内高钙浓度Ca²⁺]_i有关。

Effects of portulaca total flavone on proliferation of vascular smoothmuscle stimulated by PDGF-BB

AIM: To study the effects of portulaca total flavone (PTF) on proliferation induced by PDGF-BB of rabbit aortic smooth muscle cells(VSMCs)and explore its mechanisms. METHODS: The VSMCs of cultured organization-adherence was induced to proliferate by PDGF-BB, and effects of PTF on VSMCs was tested by cell counting method and 3H-thymidine (3H-TdR) incorporation test; The effect of PTF on cell proliferative cycle of VSMC was observed by flow cytomytry technique;The intra-cellular calcium concentration was investigated by fluorimetry.RESULTS: PTF inhibited the proliferation of VSMCs induced by PDGF-BB in a dose dependent manner,and DNA symthesis,the cells numbers of G₁/G₀ phase were increased and that of G₂/S phase were decreased markedly(P<0.01).CONCLUSION: Proliferation of VSMCs induced by PDGF-BB can be inhibited by PTF.The mechanisms may be related with diminished VSMCs Ca²⁺]_i.