Effects of magnesium-free epileptiform damage on the CREB phosphorylation in hippocampal neurons

Abstract:

Objective：To observe the expression of phosphorylated cAMP response-element binding protein（p-CREB） after epilepti－form discharge of hippocampal neurons. Methods：All cultured neurons were divided into two groups：epilepsy group：on the 10th d after the incubation，maintenance medium was replaced with magnesium-free artificial cerebrospinal fluid for 3 h；control group：on the 10th d after the incubation，maintenance medium was replaced with normal artificial cerebrospinal fluid for 3 h. Changes in ex－pressions of p-CREB and β-actin were observed by Western blot. Changes in p-CREB and neuronal nuclei（NeuN） expression was investigated by double labeled immunofluorescence. Results：Results of Western blot demonstrated that p-CREB expression was in－creased at 2 h after epileptiform discharges in epilepsy group than in control group，peaked at 6 h and maintained increased at 12 h and 24 h. Compared with that in control group，expression of p-CREB was significantly increased in epilepsy group at each time point（P＜0.01）. Immunofluorescence intensity of p-CREB was also increased significantly in epilepsy group than in control group（P＜0.01）. Conclusions：p-CREB expression in epileptiform damage neurons is significantly enhanced，which probably closely relate with epilep－tiform discharge.