缺血预处理对大鼠血管生长物质表达及新生动脉形成的影响

目的 观察缺血预处理(IPC)对促进血管新生的血管内皮生长因子(VEGF)、联合血小板源生长因子B(PDGF-B)和抑制血管新生的ADAMTS-1表达及对有功能的新生动脉形成的影响.方法 建立大鼠心脏IPC模型,通过免疫组织化学方法观察IPC后6、12、24 h VEGF、PDGF-B和ADAMTS-1的表达.在IPC后24 h建立大鼠心肌梗死模型,14 d后处死动物,通过免疫组织化学方法标记血管平滑肌细胞,观察IPC对心脏梗死区边缘成熟的新生小动脉形成的影响.对照组不进行缺血预处理,仅开胸手术24 h后取心脏组织行免疫组织化学检测或建立心肌梗死模型观察新生小动脉形成情况.结果 IPC后6、12、24 h,心肌的缺血区可见促进血管新生的VEGF和PDGF-B表达显著升高(P均<0.05),与对照组和非缺血区比较差异均有统计学意义,抑制血管生长的ADAMTS-1表达在各时间点亦可见显著升高(P均<0.05),且表达区域与VEGF和PDGF-B一致.IPC后心肌梗死14 d,可见梗死边缘区新生动脉数显著高于对照组(P<0.05).结论 IPC可以促进梗死边缘区成熟的新生动脉的形成,促血管生长的VEGF、PDGF-B和抑制血管生长的ADAMTS-1的相互调节作用可能促进了成熟的新生小动脉的形成.

Effect of ischemia preconditioning on pro- and anti- angiogenic molecule expression and functional arteries formation

Objective To observe the effect of ischemia preconditioning (IPC) on the expression of pro-angiogenic VEGF, PDGF and anti-angiogenic ADAMTS-1, and arteriogenesis. Methods Rat heart IPC model was made by 4 circles of occluding the LAD for 6 min followed by 6 min of reperfusion. The expression of VEGF, PDGF-B and ADAMTS-1 in the ischemic area was examined with immunohistochemistry at 6, 12 and 24 h after IPC. IPC plus myocardial infarction model was induced by LAD ligation 24 h after IPC, 14 days later, the anti-SM-α-actin antibody was used to detect the mature neovascularization in the border of the infracted area. Results VEGF, PDGF-B and ADAMTS-1 were significantly upregulated in the ischemic area in IPC group compared with the control group ( P < 0. 05 ).Density of mature arteries was also significantly increased in IPC plus MI group than that in MI group (P <0. 05). Conclusion IPC promoted the formation of mature new arteries which may be modulated by upregulating VEGF, PDGF-B, and ADAMTS-1 expressions.