人VEGF_(165)和bFGF基因联合治疗大鼠急性心肌梗死

目的观察直接心肌内注射人血管内皮细胞生长因子(VEGF165)和碱性成纤维细胞生长因子(bFGF)基因对大鼠急性心肌梗死模型血管及梗死面积的治疗效果,评估比较联合应用2种基因与单纯应用一种基因的疗效。方法建立大鼠急性心肌梗死模型,将生理盐水(对照组)、空载体(A组)、VEGF165(B组)、bFGF(C组)、VEGF165和bFGF混合质粒(D组)分3点注射于梗死交界处心肌内,4周后取材做常规HE染色和Masson染色,分别测量各组微血管数量和梗死面积;用免疫组织化学染色鉴定VEGF、bFGF的表达。结果B组、C组和D组心肌毛细血管总数明显大于对照组和A组(P<0.01),D组毛细血管总数大于B组和C组(P<0.01)。D组和C组的梗死面积百分比小于其他3组(P<0.01),D组和C组之间差异无统计学意义(P>0.05)。VEGF和bFGF免疫组化染色显示有相应蛋白表达。结论联合应用VEGF和bFGF基因治疗急性心肌梗死,具有明显促进血管生成、缩小梗死面积的作用。

Therapeutic Effects of VEGF165 Gene Combined with bFGF Gene for Acute Myocardial Infarction in Rats

Objective The current study was designed to explore the effect of VEGF₁₆₅ gene combined with bFGF gene on neovascularization and infarct size of ischemic myocardium by intramyocardial injection.Methods 36 SD rats were divided randomly into five groups: control group(saline group,n=6);group A(pcDNA3.1 group,n=6);group B(VEGF group,n=8);group C(bFGF group,n=8);group D(combined VEGF with bFGF group,n=8).Then they received a ligation of the left anterior descending artery to induce myocardial infarction(MI).Saline,pcDNA3.1 vector,pcDNA3.1-VEGF₁₆₅,pcDNA3.1-bFGF,and VEGF combined with bFGF was intramyocardially injected at three seperated sites into the border zone of infarction.The hearts of rats were excised to evaluate the density of the capillary vessels and infarct size by HE staining and Masson's trichrome staining after four weeks.Immunohistochemical staining was used to evaluate protein expression of VEGF and bFGF. Results The density of myocardial capillary vessels in group B((37.4±)3.0/field),group C(34.0±2.9/field) and group D((41.9±)2.9/field) was significantly more than those in control(25.2±3.2/field) and group A(25.9±3.2/field)(P<0.01).The density of myocardial capillary vessels in group D was significantly more than those in group B and C(P<0.01).There was no significant difference in infarct size between group C(27.0±4.7)% and group D((25.1±)3.1)%,but the infarct sizes of these two groups were significantly decreased compared with those of group A(38.2±7.6)%,group B(34.9±4.2)% and control(37.6±6.2)%(P<0.01).Immunohistochemical staining for VEGF appeared to be positive staining in group B and group D,and immunohistochemical staining for bFGF appeared to be positive in in group C and group D.Conclusion The therapy of VEGF₁₆₅ combined with bFGF gene promotes angiogenesis significantly and reduces infarct size.The therapy effect of VEGF₁₆₅ combined with bFGF is better than only VEGF₁₆₅ gene or bFGF gene in improving angiogenesis,as well as better than only VEGF₁₆₅ gene in reducing infarct size.