Catecholamine levels in penicillin-induced epileptic focus of the cat cerebral cortex.

In 25 cats an unilateral epileptic focus was produced by intracortical injection of potassium benzyl penicillin and on the other hemisphere, sham-operation was done by injection of the same volume of saline solution without penicillin. Catecholamine analysis was performed for each hemisphere separately. In a second series of 15 cats, the effect of catecholamines and of 1-DOPA on penicillin-induced spike activity was examined. In the first and second stage of propagation of penicillin-induced spikes, dopamine and norepinephrine significantly decreased in the focus. In the third stage no differences existed. The penicillin-induced spike activity was reduced as well by the topical application of dopamine as of 1-DOPA, whilst no inhibitory effect was observed in the topical application of norepinephrine.