Cyclic AMP levels in slices of epileptic cortex of the rat: effects of glutamate and 3-isobutyl-1-methylxanthine.

Accumulation of cyclic AMP elicited by glutamate was examined in slices from different cortical areas of rats 30 to 60 days after ferrous chloride solution was injected into the left sensorimotor cortex to induce an epileptic focus. In the anterior cortex of rats showing dominant electrographic spike activity on either side of the cortex, the glutamate-elicited accumulation of cyclic AMP was greater on the dominant side than on the other. In the anterior cortex of rats showing nearly equal spike activity on either side, the accumulation was greater on the side ipsilateral to the injection site than on the other. Different inhibitory effects of 3-isobutyl-1-methylxanthine on the elicitation of cyclic AMP accumulation by glutamate was observed in relation to the patterns of spike activity.