An important role of non-NMDA receptors in the expression of kindled amygdaloid seizure in rats.

gamma-D-glutamylaminomethylsulphonic acid (GAMS), a preferential antagonist of non-NMDA receptors (kainate and quisqualate receptors), was injected into the kindled amygdala (AM) of rats. When the kindled AM was stimulated at the previously established generalized seizure triggering threshold (GST) one hour after the GAMS (1 or 2 mumol) injection, afterdischarge (AD) generation was completely suppressed. However, a re-stimulation at the intensity of 40-200 microA above the GST generated AD associated with Stage 1 or 5 seizure. Our result suggests an important role played by non-NMDA receptors in the expression and generalization of AM-onset seizures.