Differential Effect of Swimming Stress and Exercise Models in Pentylenetetrazol Induced Kindling of Rats

Background: Epilepsy is a neurological disorder which is modulated by different situations and activities. Stress and exercise can have effects on epilepsy; it can reduce or increase its occurrence. We investigated the effect of acute and chronic stress and also regular moderate exercise on the epileptogenesis. Materials and Methods: In this experimental study, 82 male Wistar rats divided into 7 groups including 2 exercised and stressed categories, received 40 mg/kg pentylenetetrazol (PTZ) every 48 h up to 13 injections. Then the convulsive behavior was rated by Racine scale. The acute stress was applied by a 30 min swimming session in the water with temperatures of 20, 25 and 32?C. The chronic stress was created by repeated sessions of 30 min daily swimming for 5 days in 20?C water. The exercise was a 60 min swimming daily, 5 days a week and for 8 weeks in 25 and 32?C. Results: We demonstrated that the acute stress showed a decrease in kindling threshold, except for the stress in 25?C water which lowered the kindling rate. Similarly, the chronic stress decreased the kindling threshold in the first 5 injections. The exercise did not reduce the kindling threshold but did reduce the kindling rate in both 25 and 32?C water. Conclusion: It is concluded that the swimming stress enhanced the kindling process, but the swimming exercise prevented the kindling. Therefore, the animal learns to cope with the condition in a repeated regular physical activity.