【摘要】 目的 探讨超声辐照载紫杉醇微泡对大鼠血管平滑肌细胞（VSMCs）凋亡的影响及其作用机制。方法 将体外培养的大鼠胸主动脉VSMCs用血小板衍生生长因子-BB刺激后分组如下:对照组（A组）、超声辐照+微泡组（B组）、超声辐照+载紫杉醇微泡组（C组）、单纯载紫杉醇微泡组（D组）和紫杉醇组（E组）。采用频率1MHz、声强0.3W/cm²的连续波超声辐照VSMCs 120s,用流式细胞仪、Annexin V/PI染色和免疫细胞化学技术检测各组细胞周期、细胞凋亡以及凋亡相关蛋白表达的变化。结果 与A组比较,各组s期细胞比例均显著降低（P<0.01）,B组G₀/G₁期细胞比例显著增高（P<0.01）,D组和E组G₂/M细胞比例显著增高（P<0.01）,C组G₀/G₁期细胞比例和G₂/M细胞比例均显著增高（P<0.01）。与A组比较,B组和C组VSMCs凋亡率显著增高（P<0.01）,Bax蛋白表达显著上调、而Bc1-2蛋白表达则显著降低（P<0.01）。结论 超声辐照载紫杉醇微泡可诱导VSMCs凋亡,其机制可能是微泡介导的超声空化效应,致Bax蛋白表达上调及Bc1-2蛋白表达下调。更多还原

【Abstract】 Objective To investigate the effect of paclitaxel-loaded microbubbles（PLM） triggered with ultrasound irradiation on the apoptosis of rat vascular smooth muscle cells（VSMCs） and its mechanism.Methods Rat thoracic aortic VSMCs were treated by platelet derived growth factor-BB,and then randomly divided into five groups as follows:control group（group A）,microbubbles combined with ultrasound irradiation group（group B）,PLM combined with ultrasound irradiation group（group C）,PLM treated group（group D）,and paclitaxel treated group（group E）.VSMCs from groups B and C were exposed to 1 MHz continuous wave ultrasound for 120s at intensity of 0.3W/cm².The cell cycle,apoptoitc cells and the expression of Bax and Bcl-2 were detected by flow cytometry,AnnexinV/PI staining and immunocytochemical assay,respectively.Results Compared with group A,the number of the cells arrested at S phase was decreased significantly in other groups（P< 0.01）.The percentage of the cells at G₀/G₁ phase was greatly increased in group B,that of G₂/M phase cells was increased remarkably in group D and E（P < 0.01）,and those of G₀/G₁ phase cells and G₂/M phase cells were increased significantly in group C（P < 0.01）.Apoptosis rate was significantly higher in group B and C than in group A（P < 0.01）,while the expression of Bax was increased,and that of Bcl-2 decreased（P < 0.01）.Conclusion Ultrasound triggered PLM induces rat VSMCs apoptosis,which might be due to upregulation of Bax and downregulation of Bcl-2 induced by microbubbles-mediated ultrasound cavitation.更多还原