Effect of Training at Lactate Threshold Intensity on Maximal Time to Exhaustion, Depression and Anxiety Behaviour of Spontaneously Hypertensive Rats after Kainate-Induced Status Epilepticus.

AIM

The objective of the present study was to investigate the effect of treadmill training at lactate threshold intensity on maximum time to exhaustion (MTE) and heart rate (HR) as well as behavioral changes after kainate (KA)-induced status epilepticus (SE) of spontaneously hypertensive rats (SHRs).

MATERIALS AND METHODS

Male SHRs were divided in four groups: two sedentary (vehicle- and KA-treated) and two exercised (vehicle- and KA-treated), respectively. The exercised rats were trained on a treadmill at a speed of 20 m.min-1 and 0° elevation for 40 min.d-1, for 4 wk. Maximal time to exhaustion and HR was measured at the beginning and at the end of the training period. Status epilepticus was evoked in half of the sedentary and trained rats by a repetitive intraperitoneal injection of KA in low subconvulsive doses. The other half of the groups received saline. Sucrose preference test (SPT) for depression-like behavior and hole board test (HBT) for impulsivity were performed a month after KA/veh injection.

RESULTS

The maximum time of exhaustion was elongated in the SHRs at the end of the training period in comparison with the beginning. However, no effect on HR was detected in trained rats. Kainate treatment after one month of training alleviated the SE-induced anhedonia in SPT and stereotyped behavior in HBT, respectively.

CONCLUSIONS

Taken together, these results demonstrate that exercise exerts a beneficial influence on physical working capacity, depression and impulsive behavior in a co-morbid model of essential hypertension and SE.