HMGB1 involved in the activation of P38MAPK signaling pathway in the hippocampus of rats after cardiopulmonary resuscitation / 基础医学与临床

ABSTRACT

Objective_To investigate the role of HMGB1 involved in the activation of P38MAPK signal pathway in the hippocampus of rats after cardiopulmonary resuscitation.Methods_Rats were randomly divided into two groups as shame-operated group, CPR group including 2, 6, 12, 24 and 48 h after restoration of spontaneous circulation ( ROSC) (5sub-groups) .The animals were sacrificed and hippocampus were removed at the indicated time.Patholog-ical changes were examined at each time point.Calculated the brain water content by day/wet ration.The HMGB1 mRNA expression was detected by RT-PCR technique.The expressions of HMGB1 and P38MAPK activity were deter-mined using Western blot.Results_There were no histopathological change in the hippocampus of rats in shame-op-erated group, brain tissue appeared change of ischemia pathology in CPR group, it was the most severest at ROSC 24 h.The brain water content, HMGB1 mRNA in rats of CPR group increased obviously along with the prolongation of time following ROSC and reached its peak at ROSC 24 h(P<0.01),much higher than that of shame-operated group, the HMGB1 level in the hippocampus of rats after CPR significantly declined at 2 h after ROSC(P<0.01)and increased obviously at 6, 12 h and reached peak 24 h later(P<0.01), the P38MAPK activity in the hippo-campus of rats after CPR, significantly increased at 2 h after ROSC and reached peak 6 h later(P<0.01), then declined slowly later, much higher than that of shame-operated group.Conclusions_HMGB1 involved in the acti-vation of P38 MAPK signal pathway may play an important role in the early stages of brain injury after CPR.