糖尿病大鼠骨折愈合过程中 VEGF、BMP-2及BMP-7的动态观察

目的：动态观察糖尿病模型大鼠骨折愈合过程中的血管内皮细胞生长因子（ VEGF）、骨形态发生蛋白-2（BMP-2）、骨形态发生蛋白-7（BMP-7）的变化趋势，探索影响糖尿病骨折愈合的机制。方法选取Wester 雄性大鼠70只，采用随机数字表法分为糖尿病组（腹腔注射链脲佐菌素（ STZ）造模]和对照组，每组35只。采用线锯锯断2组大鼠的左侧胫骨，采用外固定复位处理，观察2组大鼠术后第1、3、5、7周的血清及骨痂中VEGF、BMP-2、BMP-7的表达变化。结果糖尿病组大鼠术后第1周、术后第3周的VEGF、BMP-2、BMP-7的表达水平均显著低于对照组（ P＜0构．05），术后第5、第7周2组大鼠骨痂组织中的VEGF、BMP-2、BMP-7的表达水平差异无统计学意义（ P ＞0．05）。糖尿病组与对照组大鼠的血清中VEGF、BMP-2、BMP-7在术后第1～7周差异无统计学意义（ P ＞0．05），糖尿病大鼠术后第1、第3周BMP-7的表达水平显著低于对照组大鼠，差异有统计学意义（ P ＜0．05）。结论糖尿病大鼠血清、骨痂组织中BMP-7、BMP-2及VEGF表达减少可能是其延迟愈合的一个重要原因。

Dynamic observation on the changes of BMP-7,BMP-2 and VEGF during fracture healing in diabetic rat models

Objective To observe dynamically the changes of vascular endothelial growth factor ( VEGF ) , bone morphogenetic protein-2 ( BMP-2) and bone morphogenetic protein-7 ( BMP-7) during fracture healing in diabetic rats,and to explore the mechanism of affecting fracture healing in diabetic rats.Methods Seventy Wistar male rats were selected in the study,according to random digits table these rats were divided into diabetes group ( n =35) in which the rats were injected intraperitoneally with streptozotocin ( STZ) to establish diabetes models, and the other 35 rats were served as control group. The left tibias of rats in both groups were sawn to break, then were treated by external fixation reduction.The changes of expression levels of VEGF,BMP-2,BMP-7 in serum and bony callus were detected and observed on 1w,3w,5w,7 w after operation.Results The expression levels of BMP-7, BMP-2 and VEGF in bony callus of diabetes group were significantly lower than those in control group on 1w,3w after operation ( P <0.05),however, there were no significant differences in the expression levels of VEGF,BMP-2,BMP-7 in bony callus on 5w,7w after operation between two groups ( P >0.05).There were no significant differences in the serum levels of VEGF,BMP-7,BMP-7 from the first week to the seventh week after operation between two groups ( P >0.05),except that the expression levels of BMP-7 in diabetes group on 1w,3w after operation were significantly lower than those in control group ( P >0.05).Conclusion The decrease of expression levels of BMP-7,BMP-2,VEGF in serum and bone callus of diabetic rats may be an important cause of delayed healing.