Expression of p38 mitogen-activated protein kinase in hippocampus CA1 and CA3 area of rats with conditioned fear

Objective To investigate the expression and activity of p38 mitogen-activated protein kinase(p38 MAPK)in hippocampus CA1 and CA3 area of rats with conditioned fear. Methods 24h after rat model of conditioned fear was established, rats were sacrificed, then expression of p38 MAPK and phosphorylated p38 MAPK (Thr180/Tyr182) in hippocampus CA1 and CA3 area of rats were detected by western blot. Results Compared with control group (ratios of value of gray scale were 1.0±0.1 and 1.0±0.2, respectively), expression of p38 MAPK and phosphorylated p38 MAPK (Thr180/Tyr182) in hippocampus CA1 area of rats with conditioned fear (9.4±2.6 and 7.8±2.1, respectively) were significantly increased (n=9, P<0.05). Compared with control group (2.1±0.5 and 1.4±0.5, respectively), expression of p38 MAPK and phosphorylated p38 MAPK (Thr180/Tyr182) in hippocampus CA3 area of rats with conditioned fear (6.2±3.3 and 2.6±0.6, respectively) were also significantly increased(n=9, P<0.05). Conclusion p38 MAPK may play important role in the formation of long term memory of conditioned fear. Key words: Conditioned fear; Memory; Hippocampus; p38 Mitogen-activated protein kinase