跑台运动对脑外伤大鼠基质金属蛋白酶-2表达的影响

摘要

目的 观察跑台训练对脑外伤大鼠基质金属蛋白酶-2(MMP-2)表达的影响.方法 55只成年Sprague-Dawley大鼠随机分为假手术组(n=15)、对照组(n=20)和运动组(n=20),后两组复制中重度脑外伤模型,运动组进行电动跑台训练1周.术后6、12、18、24 d,采用足误试验评定运动协调功能;术后48 h,采用伊文思蓝(EB)染色检测大鼠血脑屏障通透性;术后7 d,Western blot-ting检测MMP-2的表达.结果 运动组在术后6 d评分明显降低,但随后增高,其中12 d、18 d及24 d评分比对照组高(F>4.793,P<0.05);运动组EB渗出量显著减少(t=-8.091,P<0.001);运动组MMP-2蛋白表达显著下降(t=-13.12,P<0.001).结论 大鼠脑外伤后早期进行跑台训练,可改善运动功能,可能与抑制MMP-2,从而减轻血脑屏障破坏有关.%Objective To determine the effect of treadmill exercise on expression of matrix metalloproteinase-2 (MMP-2) in rats follow-ing traumatic brain injury (TBI). Methods Fifty-five male adult Sprague-Dawley rats were randomly assigned to sham (n=15), control (n=20) and exercise (n=20) groups, the later two groups subjected to unilateral cortical contusion injury (CCI). All the rats were assessed with foot-fault test 6, 12, 18 and 24 days after CCI. Evans blue perfusion was used to evaluate the integrity of the blood-brain-barrier (BBB) 48 hours after CCI. Protein expression of MMP-2 was determined with Western blotting one week after CCI. Results The score of foot-fault test improved more in the exercise group than in the control group 12, 18 and 24 days after CCI (F>4.793, P<0.05). Evans blue extravasa-tion was less in the exercise group than in the control group (t=-8.091, P<0.001), as well as the expression of MMP-2 (t=-13.12, P<0.001). Conclusion Early treadmill exercise can improve the motor function in rats with TBI, which may associate with inhibition of MMP-2 ex-pression to protect BBB integrity.