Effect of Exercise on Expression of NeuN and SynapsinI in Cortex and Cognitive Function in Rats after Cerebral Ischemia-reperfusion / 中国康复理论与实践

ABSTRACT

Objective:To observe the effect of exercise on cognitive function and the expression of NeuN and SynapsinI in prefrontal cortex of rats after cerebral ischemia-reperfusion. Methods:Forty health male Sprague-Dawley rats were randomly divided into sham group (S group, n = 10), model group (M group, n = 10), sham & exercise group (SE group, n = 10) and model & exercise group (ME group, n = 10). The left middle cerebral artery was occluded for one hour and reperfused. SE and ME groups accepted treadmill training, for 14 days. The cognitive function of rats was evaluated with open field experiment and new object recognition experiment. The number and distribution of nerve cells in rat brain were observed with Nissl staining and immunofluorescence staining. The SynapsinI expression in serum was detected with ELISA. Results:Compared with S group, the activity, times of crossing, length and activity time in central area of open field experiment decreased in M group, as well as the cognitive index and length of new object recognition experiment (P < 0.05). Compared with M group, all the indexes increased in ME group (P < 0.05). The number of Nissl bodies decreased in M group (P < 0.05) and the arrangement was disordered, while the number of Nissl bodies increased in ME group (P < 0.05) compared with M group. The NeuN positive cells was more in S group than in M group (P < 0.05), and it was more in ME group than in M group (P < 0.05); as well as that of SynapsinI. The expression of SynapsinI decreased in M group (P < 0.05), and increased in ME group (P < 0.05). Most results of behavioral experiments positively correlated with the expression of Nissl, NeuN and SynapsinI (r > 0.221, P < 0.05). Conclusion:Cerebral ischemia-reperfusion can cause cognitive impairment in rats. Exercise can alleviate nerve injury and improve cognitive function, which may relate to promoting the expression of NeuN and SynapsinI in prefrontal cortex, to increase the number of neurons and synapses.