Depolarization-elicited accumulation of cyclic AMP in slices of rat cerebral cortex with a chronic epileptic focus

Ferrous chloride solution was injected unilaterally into the sensorimotor cortex of rats to induce a chronic epileptic focus. Accumulation of cyclic AMP elicited by depolarizing agents was determined in slices from different cortical areas of rats 30-60 days after the injection. In anterior cortical areas which include the sensorimotor cortex, the cyclic AMP accumulation elicited by ouabain or a high concentration of potassium ion was greater in electrographic spike activity on the dominant side than on the other. In posterior cortical areas, no difference in cyclic AMP accumulation was detected. The regional difference in the depolarization-elicited accumulation of cyclic AMP is discussed with regard to the process of epileptic focus.