The effect of regular exercise on antioxidant enzyme activities in hippocampus after occluding one carotid in rat

Physical exercise is known to lessen vulnerability to brain damage under different pathologic conditions. The aim of this study was to investigate the protective role of regular exercise on hippocampus in hypoperfusion condition. The wistar rats were randomly divided to one four groups، control (surgery without occlusion) (first)، hypoperfusion (second)، exercise (third) and exercise –hypoperfusion (fourth) groups. Animals of third and fourth groups were made to run on treadmill for one hour once a day for two and half months. The right common carotid of animals in the fourth group was occluded after the cessation of exercise. In the second group، the right common carotid artery was only occluded and in the control group neither of these actions (applying exercise and occlusion of carotid) was done. Then the animals were sacrificed 72 hours after the occlusion and the hippocampal enzyme activities (total antioxidants، catalase and superoxide dismutase) were measured by ELISA method. The exercise significantly increased the total antioxidant enzyme activities in left hippocampus of fourth group in comparison with second and control groups. The superoxide dismutase activity was decreased significantly in the second group in comparison with control and the exercise successfully returned these activities to normal level in the fourth group. The exercise increased catalase activity in hippocampi of fourth group to the control and second groups. There was no significant difference of superoxide oxidase and catalase activitie between hemispheres in every group (p<0. 05)، but the difference of total antioxidant activities between hemispheres in the fourth group was significant. This study showed that exercise has prventive role in hippocampus by increasing antioxidant enzyme activities especially superoxide enzyme in brain 3 days after occluding right carotid. More studies are needed for clarifying of its mechanism.