[Epileptogenic properties of quisqualic acid: microinjection into the unilateral amygdala in cats].

The present studies demonstrated that the microinjection of quisqualic acid (QA) into unilateral amygdala in chronically implanted cats resulted in various types of limbic seizures in accordance with injected doses. The epileptogenic potency of QA in the induction of epileptic seizures was lower then that of kainic acid (KA), which has also been demonstrated in our previous studies. Electroencephalographic changes and clinical manifestations of QA-induced epilepsy were less prominent as compared with those of KA-induced epilepsy. Five micrograms of QA resulted in pure amygdaloid seizures. The moderate dose administration of QA (15 micrograms) was suitable to observe limbic status. Both doses of QA elicited similar characteristic epileptic patterns on EEG, which was quite distinguishable from those of KA. In pathological study, mild degeneration of hippocampal pyramidal cell layer was observed in the cases injected 15 micrograms of QA. These electro-clinical and pathological features are interesting in similarities to those of human complex partial seizures, mesial temporal sclerosis. In conclusion, the strict dose dependency of QA in the production of limbic seizures is a valid advantage for an experimental model of a complex partial epilepsy in man.