运动训练对小鼠脑局灶缺血后大脑皮质一氧化氮合酶的影响

目的：研究运动训练对小鼠大脑中动脉闭塞（MCAO）后大脑皮质一氧化氮合酶（NOS）的影响。方法：30只雄性C57 BL/6J鼠用Bederson的方法，建立MCAO模型。将MCAO后小鼠随机分为运动组和对照组，每组均15只鼠。运动组：跑笼训练共90d；对照组：跑笼固定不转。分别在MCAO后15d、45d、90d，观察两组小鼠大脑皮质NOS数的改变。结果：MCAO后15d，两组皮质缺血侧、正常侧NOS阳性细胞数差异无显著性意义（t=2．1，0．2，P〉0．05）。45d，运动组比对照组在皮质正常侧NOS阳性细胞数显著增高（t=3．55，P〈0．05），缺血侧差异无显著性意义（t=0．26，P〉0．05）。90d，运动组与对照组比较，NOS阳性细胞计数在正常侧皮质均差异有显著性意义（P〈0．01），而缺血侧各组之间差异无显著性意义（P〉0．05）。结论：运动训练可增加小鼠MCAO后大脑正常侧皮层NOS阳性细胞的数量，对脑的可塑性有一定促讲作用.

Physical exercise effects on the nitric oxide synthase after middle cerebral artery occlusion in mice

Objective:To investigate the impact of a moderate amount of physical training on the amount of nitric oxide synthase(NOS) after middle cerebral artery occlusion(MCAO) in mice. Method: Thirty male C57 BL6J mice underwent MCAO(described by Bederson JB et al )and then divided into training group(n=15) and control group(n=15).The mice of experiment group were trained with voluntary running wheel for one hour daily (6 days per week) for 90 days. The running wheel of the control group was fixed. Fifteen days, 45 days and 90 days after MCAO, the amount of NOS-positive neurons were respectively calculated in lesion and normal sides of the cerebral cortex. The design of the study was completely randomized between the two groups. T-test were performed. Result: There was no difference in the number of NOS positive cells in two sides of cortex between training and control group in 15 days after MCAO(t=2.1 and 0.2,P>0.05.In 45 days after MCAO, The amount of NOS-positive neurons in normal side in cortex showed a significant increase in training group than it in control group(t=3.55,P<0.05),but not significant in lesion side(t= 0.26,P>0.05).In 90 days after MCAO, comparison between training group with control group showed the amount of NOS-positive neurons increased in cortex in normal side(t=6.53,P<0.05). Conclusion: The physical training can modify the amount of NOS-positive neurons on the normal side of cerebral hemispheres in mice after MCAO.