The Relationship Between P53Expression And Mossy Fiber Sprouting Of Hippocampus In PTZ Kindling Model

Object To observe the expression changes of P53protein in the CA1,CA3and dentate gyrus of hippocampus associated with the changes of hippocampal mossy fiber sprouting in the pentylenetetrazole (PTZ) kindling model and to investigate the role of P53in epileptogenesis.Methods90healthy male Sprague-Dawley rats were divided randomly into control and PTZ treated groups. The PTZ treated rats were intraperitoneally injected PTZ (30mg/kg) every24hours and stopped injection once they were kindled. The control rats were intraperitoneally injected0.9%saline at the same time. Seizure manifestations were evaluated according to Racine. At3d,1w,2w,4w,6w after the first PTZ injection, Timm staining was scored at different times in the CA3and dentate gyrus of hippocampus. The protein of P53was analyzed at different times in the CA1,CA3and dentate gyrus of hippocampus, by using immunohistochemistry.Results1.Animal model:Subsequent injection with the same dose of PTZ induced convulsive responses with gradually increasing severity. After21-28days injection(24.5±2.3days),100%animals were kindled, the mortality is2.2%. The control rats have no seizure.2.Changes of hippocampal mossy fiber sprouting:The Timm scores in the CA3region, which gradually increased from3d, got the highest score at6w. It was significantly higher than that in controls at2w,4w,6w. Compared with the control groups,the timm scores in the dentate gyrus region of the PTZ treated groups, which gradually increased from4w, got the highest score at6w. It was significantly higher than that in controls at4w,6w(P<0.05). In control groups,the timm scores in the CA3region only0～1point, there was no significant difference at different times.The dentate gyrus region found no moss fiber budding at each time point.3.Changes of P53protein expression:The expression of P53in the CA1,CA3and dentate gyrus of hippocampus has no dynamic change in the pentylenetetrazole (PTZ) kindling model. There was no statistically significant difference between two groups.4. The correlation analysis between the expression of P53protein and MFS in hippocampus:The expression changes of P53protein and the changes of mossy fiber sprouting in hippocampus of PTZ kindling model have no correlation.ConclusionThe expression of P53protein in hippocampus has no relationship with MFS in the PTZ kindling model.