REGIONALLY SELECTIVE STIMULATION OF MITOGEN-ACTIVATED PROTEIN (MAP) KINASE TYROSINE PHOSPHORYLATION AFTER GENERALIZED SEIZURES IN THE RAT-BRAIN

Immunoblot analysis using a phosphotyrosine-specific antibody was perf ormed to investigate tyrosine phosphorylation of the mitogen activated protein (MAP) kinase in the rat brain. Epileptic seizures induced by systemic injection of bicuculline caused a rapid and transient stimula tion of MAP kinase tyrosine phosphorylation in hippocampus and somatos ensory cortex. This increase in tyrosine phosphorylation was markedly attenuated by the N-methyl-D-aspartate (NMDA) receptor antagonist MK-8 01. In contrast, in the cerebellum, tyrosine phosphorylation of MAP ki nase remained undetectable after bicuculline-induced seizures. These r esults demonstrate that generalized seizures stimulate tyrosine phosph orylation of MAP kinase in a regionally selective manner.