Abstract:

Objective: To observe the effect of rimonabant on the susceptibility of epilepsy in the rats after head injury,and to explore whether rimonabant can block epilepsy in the rats after head injury. Methods: A total of 105 rats were divided into model-management group (n=45),model group (n=45), and blank control group (n=15).The rats in model-management group and modeling group were used to establish the traumatic head injury models by fluid percussion injury (FPI) method,and the rats were intraperitoneally administered with rimonabant and saline 2 min after FPI,respectively.The rats in model and model-management groups were intraperitoneally injected with pentylenetetrazole at 24 h,1 week, and 6 weeks after FPI.The rats in blank control group were also intraperitoneally injected with pentylenetetrazole.The latency of epilepsy and the number of generalized tonic clonic seizures(GTCS) of the rats in each group were observed and compared. Results: In model group,the latency of epilepsy of rats at 6 weeks after PFI was obviously shorter than those at 24 h after FPI(F=12.93,P=0.023) and 1 week after FPI(F=11.80,P=0.016).However,in model-management group,the latency of epilepsy of the rats at 24 h after PFI was shorter than those at 1 week after FPI(F=14.69,P=0.024) and 6 weeks after FPI(F=11.69,P=0.024).The latency of epilepsy of the rats in blank control group was longer than those at 6 weeks after FPI in model group(F=14.74,P=0.03) and at 24 h after FPI in model-management group(F=18.33,P=0.007).The latency of rats in model group at 24 h after FPI was longer than that at 24 h after FPI in model-management group(t=2.97,P=0.009);the latency at 6 weeks after FPI in model group was shorter than that at 6 weeks after FPI in model-management group (t=2.31,P=0.033). The number of rats with GTCS in model-management group was decreased at 6 weeks after FPI than that in model group(χ²=6.67,P=0.033). Conclusion: The rimonabant can increase the susceptibility of epilepsy in the acute stage of head injury and plays an opposite role in the chronic stage.

Key words: rimonabant, head injury, epilepsy, endocannabinoid, CB1 receptor