VSMCs apoptosis occurred in vascular media at 3 days after balloon injury and reached a peak in media and intima where apoptosis was mainly present at 7 days, then decreased.

• 球囊损伤内皮后第 3d ,血管中层出现凋亡的SMC ; 损伤后第 7d ,内膜和中层SMC凋亡率最高 ,凋亡的SMC主要分布在内膜层 ;