MK-801 DOES NOT ATTENUATE IMMEDIATE-EARLY GENE-EXPRESSION FOLLOWING AN AMYGDALA AFTERDISCHARGE

It has been suggested that the increased transient expression of immed iate-early gene transcription factors seen in nerve cells following an afterdischarge may initiate longer lasting or permanent changes in ge ne expression which underly the development of kindling. Since the dev elopment of kindling is sensitive to pharmacological blockade of the N -methyl-D-aspartate receptor, we tested whether the increased expressi on of the immediate-early genes c-fos, jun-B, c-jun, krox-20, and krox -24 following a kindling afterdischarge was also sensitive to N-methyl -D-aspartate receptor blockade by MK-801. In this report we demonstrat e that all five immediate-early genes are induced by an amygdala after discharge. N-methyl-D-aspartate receptor blockade by a dose of MK-801 that significantly retards the development of amygdala kindling failed to attenuate immediate-early gene expression. These results suggest t hat although expression of these five immediate-early genes occurs aft er an amygdala afterdischarge their expression is not involved in the N-methyl-D-aspartate receptor-mediated component of amygdala kindling. (C) 1994 Academic Press, Inc.