Bidirectional transhemispheric interaction between amygdaloid kindling induced by excitatory amino acids and electrical stimulation.

Using transhemispheric transfer and post-transfer interference as specific measures, the relationship between chemical and electrical kindling at the amygdala (AM) in rats was examined. Chemical kindling was accomplished by repeated injections of a subconvulsive dose of combined L-glutamate (GLU) and L-aspartate (ASP) in a molar ratio of 1:3 (GLU 0.375 microM:ASP 1.125 microM). Strong bidirectional transhemispheric transfer between electrical and chemical kindling occurred at the secondary-site AM. In addition, at the primary-site retest, bidirectional posttransfer interference between electrical and chemical kindling was observed. These findings strongly suggest that endogenous GLU/ASP participates in the transsynaptic changes which are presumed to underlie the kindling phenomenon.