Anticonvulsants mechanism of action

The results demonstrate anticonvulsant properties of PCP and ketamine in two quite different seizure models. On the one hand, ketamine was effective in antagonizing several components of PTZ activity. Others have previously reported anti-PTZ effects of ketamine. However, the present results demonstrate that the anticonvulsant effects of ketamine against PTZ seizures closely resembled the effects of phenobarbital in that both compounds delayed clonic convulsions and prevented tonic extension. Moreover, a low dose of ketamine, which alone showed no anticonvulsant effect or overt behavioral changes, potentiated the anti-PTZ effects of phenobarbita 1. These findings suggest that ketamine possesses selective anticonvulsant properties. The anticonvulsant mechanism of action for phenobarbital is not known. However, the similarities between ketamine and phenobarbital, and the interaction between the two compounds, suggest a common mechanism or site of acti on. 

McLean, M.J., MacDonald, R.L. (1986). Limitation of sustained high frequency repetitive firing a common anticonvulsant mechanisms of action. In Neurotransmitters, Seizures and Epilepsy III (G. Nistico, P.L. Morselli, K.G. Lloyd, A.G. Fariello, J. Engel, Jr., eds), pp. 23 1. Raven Press, New York. 

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