钙蛋白酶在脊髓缺血再灌注损伤中的表达

Increased calpain expression and activity in spinal cord ischemia-reperfusion injury: Experimental study

要目的探讨脊髓缺血再灌注损伤后,钙蛋白酶在脊髓组织中的表达及缺血再灌注损伤对脊髓摘运动功能的影响。方法纯种雄性成年SD大鼠,夹闭右肾动脉分支下方腹主动脉30min,观察再灌注后3、24、72h和7d时脊髓损伤节段的钙蛋白酶Ⅰ的表达,钙蛋白酶特异性底物68-KDNFP的降解以及再灌注后72h的动物后肢功能评分。结果动物脊髓再灌注损伤后3h,开始出现的钙蛋白酶Ⅰ阳性细胞,并且随着时间的延长,阳性细胞数目逐渐增多,染色深度逐渐增加,再灌注后72h最明显,与对照组相比,具有显著性差异(P<0.01)。68-KDNFP的降解产物也在再灌注损伤后3h出现,并且随着时间的延长逐渐加重,并在72h后达到高峰。再灌注后72h后肢功能出现不同程度的运动功能障碍。结论大鼠脊髓缺血再灌注损伤后出现钙蛋白酶Ⅰ的大量表达,特异性分解细胞骨架蛋白68-KDNFP,并且会引起动物后肢一定程度的功能障碍。

Objective To observe the calpain expression and activity in rat spinal cord and investigate the function of hind-limb after ischemia-reperfusion injury.Methods The abdomial aorta of male Sprague-Dawley (SD) rats were clipped for 30 minutes and then reperfused for 3 hours, 24hours, 72hours or 7days.The expressed calpain-in the attached segment of spinal cord was indicated with immunohistochemistry stain. Western Blot analysis of 68-KD NFP was used to indicate the activity of calpain. After 72 hours of reperfusion, the motor function score of hind-limb was observed.Results The immunohistochemistry stain of calpain-was found and 68-KD NFP was degradated in the spinal cord sections after 3 hours of reperfusion and peaked after 72 hours.Statistical analysis showed significant differences between the control group and the ischemia-reperfusion group.After 72hours of reperfusion, the motor function of hind-limp in the ischemia-reperfusion group had a low function score.Conclusion An early increased calpain-expression and activity was found in rat spinal cord after ischemia-reperfusion, thus inhibition of the expression and activity could provide neuroprotection in ischemia-reperfusion spinal cord.