y射线照射对平滑肌细胞增殖及凋亡的影响

Effect of y-radiation on proliferation and apoptosis of smooth muscle cells

目的 探讨近距离腔内放射治疗预防血管成行术后再狭窄的机理。方法 培养的动脉平滑肌细胞分别接受吸收剂量为 3 5、7 0、14和 2 8Gy60 Coγ射线照射 ,12h后以流式细胞仪检测细胞各周期百分率及凋亡率。结果 吸收剂量为 3 5、7 0、14和 2 8Gy组的G0 ～G1期细胞数分别占细胞总数的 5 8 13%、83 6 %、88 79%、89 15 % ,与对照组 (5 6 2 9% )相比 ,7 0、14、2 8Gy组差异有非常显著性 (P <0 0 1) ;而 3 5Gy组差异无显著性 (P >0 0 5 ) ;照射各组细胞凋亡率分别为0 85 %、1 0 4%、10 38%、16 0 0 % ,与对照组 (0 84% )相比 ,14、2 8Gy组差异有非常显著性(P <0 0 1)。结论 3 5Gy60 Coγ射线照射对血管平滑肌细胞的增殖和凋亡均无影响 ,7Gy能抑制细胞增殖 ,但对细胞凋亡无显著影响 ,而 14和 2 8Gy既能抑制细胞增殖 ,又能诱导细胞凋亡。

Objective To study the molecular mechanism of endovascular brachyterapy to reduce restenosis after coronary artery balloon angioplasty. Methods The cultured vascular smooth muscle cells (VSMC) were irradiated with 3 5,7,14,28 Gy 60 Co γ rays, respectively. The cell cycle and apoptosis of smooth muscle cells (SMC)were determined by flow cytometry at 12 h after brachytherapy. Results The percentages of G 0-G 1 phases were 58 13%,83 6%,88 79% and 89 15%, respectively in irradiation groups.Compared with the control group (56 29%), the proliferation of SMC was inhibited significantly by irradiation with 7,14,28 Gy 60 Co γ rays (P<0 01) .The percentages of apoptosis were 0 85%,1 04%, 10 38%,16 00% in irradiation groups, respectively. Compared with the control group (0 84%), apoptosis was induced significantly by 14, 28 Gy γ irradiation (P<0 01) . Conclusion The irradiation dose of 3 5 Gy 60 Co γ rays can neither inhibit proliferatrion nor induce apoptosis of SMC, 7 Gy can inhibit proliferation, but cannot induce apoptosis, whereas 14,28 Gy can both inhibit proliferation and induce apoptosis of SMC.