c-myc基因表达对移植静脉平滑肌细胞增殖的影响

检测不同时期移植静脉平滑肌中ｃ－ｍｙｃ基因表达情况，探讨基与移植静脉ＳＭＣ增殖的关系。方法建立大鼠自体静脉移植模型，分别于手术后３０分钟、２、６、４８小时，１、２、４周切取移植静脉，应用免疫组织化学及原位杂交方法观察不同时期移植血管ＳＭＣ中增殖细胞核抗原（ＰＣＮＡ）、ｃ－ｍｙｃ基因表达情况。结果ｃ－ｍｙｃｍＲＮＡ于术后２、６小时明显升高，与３０分钟比较差异有非常显著意义（Ｐ〈０．０１）；ＰＣＮＡ，

Effect of expression of cmyc gene on hyperplasia of smooth muscle cells in vein graft in rat

Objectives To analyse effect of expression of cmyc gene on hyperplasia of smooth muscle cells in vein graft and evaluate the effect of cmyc gene on intimal hyperplasia of vein grafts. Methods We transplanted the autologous internal jugular vein on iliac artery by end to end anastomosis in rat. The vein grafts were harvested at 30 min, 2 h, 6 h, 2 days, 1 week, 2 weeks and 4 weeks after grafting and were rapidly frozen in liquid nitrogen. Proteins of PCNA and cmyc were detected in the different time with method of immunohistochemical staining (SP) and cmyc mRNA with in situ hybridization. Staining result was measured by microscope (400X). Results Freshly harvested veins did not demonstrate PCNA, cmyc protein production and cmyc mRNA. Staining for cmyc mRNA was significantly higher at 2 h, 6 h compared with that at 30 min (P<0.01). Staining for PCNA, cmyc protein production peaked at 1 week (44.88.2)%, (16.23.2)%, respectively) and was significantly higher than that at 6 h (3.20.7)%, (4.10.9)%, respectively) (P<0.01). Conclusion cmyc is expressed early after experimental vein grafting, with peak at 1 week paralleled with PCNA. This occurs during a period of maximal SMC proliferation, and increased expression of PCNA. Expression of cmyc gene may contribute to the induction and regulation of SMC proliferation.