局部分次注射外源性VEGF影响大鼠放疗皮瓣成活性的实验研究

Effect of extrinsic vascular endothelial growth factor (VEGF) on the viability of rat skin flap received radiotherapy

目的:探讨单次与分次局部皮下注射相同剂量的血管内皮细胞生长因子(vascular endothelial growth factor,VEGF)对大鼠背部放疗皮瓣成活的影响。方法:40只Wister大鼠随机分成4组,背部做3cm×4cm带蒂皮瓣,术后2、4、6d60Co照射。A组术后3、5、7d每天注射80ng/只VEGF;B组第3天,一次性注射240ng/只;C组与A组对照,D组与B组对照,在相应时间注射等量生理盐水。采用肉眼观察、病理学观察、荧光染色结合Photoshop图像色彩分析及组织琥珀酸脱氢酶(SDH)活力测定等方法对皮瓣活性进行比较。结果:A组皮瓣血管面积比大于B组(P<0.05),A组与C组比较差异有显著性(P<0.01);B组与D组亦有差异(P<0.05);荧光染色见,A组皮下血管网密度大于B组;琥珀酸脱氢酶测量显示,分次给药组的皮肤组织活力大于单次给药组(P<0.05)。结论:分次给予有效剂量VEGF,皮瓣微血管生成状况比一次给大剂量效果更好。

Objective： To observe the relationship between the vascular endothelial growth factor （VEGF） and the survival of flap in the rat back which received radiotherapy. Methods： Forty Wistar rats were divided into four groups. A 3 × 4 cm2 full thickness dorsal flap with pedicle was prepared at the posterior end. The skin flaps were given 60Co radiotherapy in the 2, 4, 6 day postoperation. Group A was given of VEGF in the third, fifth, seventh day. Group B was given a high quantity of VEGF. Group C was the control of Group A, Group D was the control of Group B. Control groups received normal saline. Results ： Pathological observation revealed that the survival of flap and blood vessel lumen diameter of group A were higher than that of group B （ P 〈 0.05 ）. Group A showed remarkable difference compared with group C（ P 〈 0.01 ）. Group B showed remarkable difference compared with group D（ P 〈 0.05 ）. Resuits of fluorescence staining and SDH examination showed that three times injection had better results than one time injection. Conclusion ： Three times injection of VEGF has better effect on the viability of rat skin flap than one time injection.