Effects of drugs influencing the cAMP level on hippocampal seizure activity.

Changes of hippocampal EEF seizure activity elicited by electrical stimulation of the hippocampus or penicillin injection into the hippocampus were investigated under the effect of locally applied drugs influencing the cAMP level in the brain. It was observed that some drugs which elevate the cAMP level such as papaverine, histamine +K+ and dibutyryl cAMP elevated the electric seizure threshold while in penicillin-induced epilepsy they reduced the occurrence of ictal activity and the interictal spike frequency. These drugs when applied before penicillin prolonged the time necessary for development of the epileptic focus. The effect of imidazole was the opposite in every respect. On the basis of these data the possible role of cAMP in the pathomechanism of epilepsy is discussed.