Photically induced epilepsy in Papio papio as a model for drug studies.

Neurophysiological studies employing drugs have been undertaken in the natural syndrome of photically induced epilepsy in the Senegalese baboon Papio papio. GABA-mediated inhibition, both pre- and posysynaptic, plays an important role in the epileptic manifestations seen in this syndrome synapses can significantly modify photically induced epileptic responses, partly as a result of changes in afferent activity. The level of activity in dopaminergic systems can also modify the epileptic signs. Among anticonvulsant drugs, barbiturates and benzodiazepines are very effective against this type of epilepsy, whereas many other drugs are weakly active or toxic. A modification of the natural model (using allylglycine as a priming agent) is convenient for correlating acute anticonvulsant activity and neurological toxicity with plasma concentrations of anticonvulsant agents.