血管内皮生长因子在大鼠持续性脊髓压迫伤中的表达

目的研究血管内皮生长因子(VEGF)在实验大鼠持续性脊髓压迫伤中的表达变化,并探讨其在脊髓压迫伤中的作用和意义。方法健康封闭群W istar大鼠60只,体重280~300 g,采用平头塑料螺钉后路压迫复制大鼠持续性脊髓压迫伤的动物模型(脊髓50%压迫)。以改良Tarlov评分、BBB-21点评分及斜板实验评价其后肢运动功能;应用免疫组织化学和原位杂交技术,检测脊髓组织在持续性压迫适应中不同时段VEGF-mRNA和蛋白的表达,并结合计算机图像分析仪进行定量分析。结果持续压迫各时间组大鼠后肢功能明显减弱,在压迫2 d组大鼠的后肢功能进一步恶化,随着持续压迫时间的推移,大鼠脊髓运动功能有一小幅度的自发性恢复,在持续压迫3周左右时恢复较明显。VEGF的mRNA和蛋白在损伤脊髓组织中广泛表达,压迫1 d组出现大量的免疫阳性细胞,压迫2d组VEGF表达强度达高峰,压迫1周组表达明显下调(P<0.05),压迫3周时降至基础水平。结论在实验大鼠持续性脊髓压迫损伤的发生与发展中,VEGF的表达可能参与了脊髓组织的缺氧耐受及损伤后的修复。

Expression of vascular endothelial growth factor in spinal cord continuous compression injury

ObjectiveTo investigate the expression changes and effects of vascular endothelial growth factor(VEGF) in rats' spinal cord continuous compression injury.MethodsThe model with spinal cord continuous compression injury was made by compressing the posterior of spinal cord with a blunt plastic screw.Sixty Wistar male rats were randomly divided into compression group and control group.Changes of the behavior and hind-limb function of experimental rats were observed.The expression changes of vascular endothelial growth factor at various times were detected at the level of mRNA and protein by hybridization in situ and immunohistochemistry. ResultsThe hind-limb function of experimental rats weakened significantly,further deteriorated after 2 days,and recovered slightly following the time going on and obviously after 3 weeks.VEGF expressed more significantly at the level of mRNA and protein in injured spinal cord of experimental group than in the spinal cord of control group(P<0.05),peaked after 2 days,decreased significantly after 1 week(P<0.05),and disappeared after 3 weeks.ConclusionVEGF expression might play a role in hypoxia tolerance and repair for spinal cord continuous compression injury.