Diphosphorylation of extracellular signal-regulated kinases and c-Jun N-terminal protein kinases in brain ischemic tolerance in rat

Extracellular signal-regulated kinases (ERKs) and c-Jun N-terminal protein kinases (JNKs) activation in brain ischemic tolerance were examined by West ern immunoblot. ERK but not JNK diphosphorylation (activation) were increas ed after preconditioning ischemia. The increased JNK1 but not ERK diphospho rylation after lethal ischemia was eliminated by pretreatment with precondi tioning ischemia. The results suggest that the elimination of JNK1 activati on after lethal ischemia by preconditioning ischemia may be one of the impo rtant protective mechanisms in ischemic tolerance, and ERKs activation may be involved in the induction of the protective responses. (C) 2000 Elsevier Science B.V. All rights reserved.