Influences on ERK signal transduction pathways to nerve cell apoptosis in rats after trauma

Objective To study the mechanism of ERK signal transduction pathways to nerve cell apoptosis in rats after trauma.Methods Heavy diffuse brain injury(TMI) model was established.Male SD rats(n = 70) were randomly divided into two groups: trauma group and control group.Tuma group was divided into 7 subgroups according to time phase following brain injury: 10,30 min,3,6,24,48,72 h.The expression of p-ERK1/2 and caspase-3 were detected by immunity histochemistry staining;the apoptosis of nerve cell was detected by TUNEL.Results The expression of p-ERK1/2,caspase-3 in the hippocampasl CA1 area in TBI group were increased significantly after injury 3 h compared to those in the control group(P 0.05),and reached the peak at 6 h(P 0.01),the overexpression of p-ERK1/2 and caspase-3 continued to 24 h and 72 h respectively;TUNEL positive cells were increased in TBI group from 3 h to 72 h,and reach the peak at 48 h(P 0.01).Conclusion The activation of ERK signal transduction pathway and expression of caspase-3 may is one of mechanisms of nerve cell apoptosis following traumatic brain injury in rats.