三氧化二砷对球囊拉伤后兔血管平滑肌细胞作用的实验研究

目的　探讨三氧化二砷对球囊拉伤后兔髂动脉血管平滑肌细胞的促凋亡作用及其对再狭窄防治的意义。方法　贴块法行球囊拉伤后兔髂动脉血管平滑肌细胞培养 ,将细胞分为正常对照组 ,三氧化二砷 (浓度分别为 1 0、2 0、3 0、4 0及 5 0 μmol/L)组 ,通过绘制细胞生长曲线、DNA电泳、透射电镜、原位细胞凋亡检测试剂盒 (TUNEL)来观察三氧化二砷促细胞凋亡作用。结果　随三氧化二砷浓度的增加它能够抑制细胞的增殖并且该作用与时间及三氧化二砷浓度呈正相关 ,观察第7天、浓度为 5 0 μmol/L时活细胞数为 (5 30± 0 10 )× 10 5/ml与正常对照组 (2 8 77± 0 93)× 10 5/ml相比较差异有显著意义P <0 0 5 )。透射电镜下可见凋亡小体、DNA电泳可见典型凋亡后梯形条带、TUNEL可见凋亡细胞由 18 0 %± 3 1%增至 39 8%± 2 7% (P <0 0 5 )。正常对照组均不见上述变化。结论　三氧化二砷可促进球囊拉伤后兔髂动脉血管平滑肌细胞的凋亡 ,抑制其过度增殖。

Effect of arsenic trioxide on rabbit vascular smooth muscle cells after balloon angioplasty

OBJECTIVE: To study the apoptotic effect of arsenic trioxide on rabbit vascular smooth muscle cells (RVSMCs) after balloon angioplasty. METHODS: A New Zealand rabbit underwent balloon angioplasty three times at one of its iliac arteries. The iliac artery at the opposite side was used as control. Three days after the rabbit was killed. The VSMCs of the iliac artery undergoing balloon angioplasty were cultured. Arsenic trioxide of different concentrations was added into the culture. VSMCs not co-incubated with arsenic trioxide was used as controls. Cell proliferation curve was drawn. DNA was extracted and underwent electrophoresis. Transmission electron microscopy was used to observe the ultramicroscopic structure. TUNEL technique was used to examine the apoptosis of cells. RESULTS: Cell proliferation curve showed that the control cells grew geometrically and reached a plateau stage by day 3. The cells co-incubated with arsenic trioxide proliferated more slowly and the plateau stage appeared earlier dose-dependently (P < 0.05). Electrophoresis showed obscure ladder band of DNA specific to cell apoptosis, especially at the concentrations of arsenic trioxide of 3.0 and 4.0 micro mol/L. Transmission electron microscopy showed apoptotic cells with apoptosis nodes. TUNEL technique showed that the number of yellow-dyed cells was significantly larger after the addition of arsenic trioxide. The above-mentioned manifestations were not seen in the control group. CONCLUSION: Arsenic trioxide increases the apoptosis of rabbit vascular smooth muscle cells after balloon angioplasty and inhibits RVSMCs over-proliferation. It is a hopeful measure in prevention of re-stenosis after angioplasty.