The changes of NR2B expression in the striatum of rats with chronic alcohol exposured at different withdrawal time / 中华行为医学与脑科学杂志

ABSTRACT

Objective To observe the changes of N-methyl-D-aspartate (NMDA) receptor 2B subunit (NR2B) expression in the striatum of chronic alcohol exposured rats at different withdrawal time.Methods 72 male Wistar rats were randomly divided into withdrawal 2h group,withdrawal 6h group,withdrawal 12h group,withdrawal 1d group,withdrawal 3d group and control group,and 12 rats in each group.In the 5 withdrawal groups,ethanol was administered in drinking water at the concentration of 6％ (V/V) for 16 weeks,and rats in control group were maintained with water.After 16 weeks ethanol was removed and ethanol withdrawal syndromes were evaluated.The expression of NR2B protein in the striatum was measured by immunofluorescence and western blot and the expression of NR2B mRNA in the striatum was measured by realtime PCR.Results Compared with withdrawal scores of control group((1.50±0.80)),scores of withdrawal 2h,6h,12h,1d,3d groups ((10.42±2.50),(15.42± 1.93),(9.25±2.01),(7.67± 1.92),(2.25±0.87) respectively) were higher,and the withdrawal scores of withdrawal 6h group were the highest.Compared with the expression of NR2B fluorescence intensity (2210.00± 178.20),the expression of NR2B protein(0.150±0.009) and the expression of NR2B mRNA(0.006±0.001) in the striatum of control group,the expression of NR2B fluorescence intensity (2710.56 ± 194.21),(5035.16 ± 234.41),(3326.23 ± 378.16),(2570.64 ±177.88),the expression of NR2B protein (0.192±0.008),(1.649±0.205),(0.783±0.109),(0.180±0.009) and the expression of NR2B mRNA (0.026±0.002),(0.351±0.034),(0.248± 0.023),(0.024±0.003) of withdrawal 2h,6h,12h,ld groups were significantly higher (P＜0.05),and with the extension of the withdrawal time,the expression was gradually increased.The expression of withdrawal 6h group was the highest,then began to decline,and returned to baseline levels at withdrawal 3 d(P＞0.05).Withdrawal scores were positively correlated with the expression of NR2B protein(r=0.719,P＜0.01),the expression of NR2B protein was positively correlated with the expression of NR2B mRNA(r=0.937,P＜0.01),and the expression of NR2B mRNA was positively correlated with withdrawal scores(r=0.673,P＜0.01).Conclusion The expression of NR2B was up-regulated in the striatum of chronic alcohol exposured rats at different withdrawl time.NR2B protein and NR2B mRNA expression is positively correlated with the withdrawal scores,suggesting that regulating the expression of NR2B may be a new target for the treatment of ethanol withdrawal symptoms.