鞘内注射NOS抑制剂对吗啡戒断大鼠脊髓神经元磷酸化CREB表达的影响

摘要

目的 研究鞘内注射NOS抑制剂对吗啡依赖大鼠纳洛酮催促戒断反应、脊髓p-CREB表达的影响.方法 建立大鼠吗啡依赖和戒断模型,SD大鼠72只,分为正常对照组、吗啡依赖组、吗啡戒断组、L-NAME组,每组18只大鼠.采用行为学(n=8)、免疫组织化学(n=6)和Western blot (n=4)方法观察鞘内注射L-NAME对吗啡依赖大鼠纳洛酮催促戒断反应、脊髓p-CREB表达的影响.结果 (1)鞘内注射L-NAME、可明显减轻吗啡依赖大鼠戒断症状,戒断组戒断症状评分为28.60±4.89,L-NAME组22.10±4.52(P<0.05);戒断组TEA评分为13.50±2.55,L-NAME组9.80±3.11(P<0.05).(2)鞘内注射L-NAME可明显减少戒断大鼠脊髓背角p-CREB阳性神经元的数目(380±71),L-NAME组(283±47)低于戒断组(P<0.05).(3)Western blot 结果显示:鞘内注射L-NAME明显抑制吗啡戒断期间脊髓p-CREB表达的增加.结论 鞘内注射NOS抑制剂能明显抑制吗啡戒断大鼠脊髓神经元p-CREB的表达.%Objective To explore the effects of intrathecal injection of NOS inhibitor L-NAME on morphine withdrawal response and the spinal phospho-CREB expression in morphine-induced withdrawal rats.Methods Morphine dependence and withdrawal models were developed.72 SD rats were divided into 4 groups: control group, dependence group, withdrawal group, LNAME group, 18 rats for each group. Praxiologic assay (n=8) , immunohistochemical method (n=6) and Western-blotting technique (n =4) were used to evaluate morphine withdrawal response and the expression of phospho-CREB in the spinal cord.Results The results showed that intrathecal injection of NOS inhibitor significantly alleviated morphine withdrawal symptoms.Morphine withdrawal scores in L-NAME group(22.10±4.52) were significantly lower than that of withdrawal group(28.60±4.89) (P＜0.05) ;TFA score of withdrawal group was (13.50±2.55) , which was significantly higher than that of L-NAME group (9.80±3.11 ,P＜0.05). Phospho-CREB positive neurons in the spinal dorsal horn of withdrawal group were 380±71 , which was higher that of L-NAME group (283±47,P＜0.05).Compared with withdrawal group, level of phospho-CREB protein detected by Western blot in spinal cord of L-NAME group were significantly lower.Conclusion The NOS inhibitor can significantly suppress expression of phosphoCRFB in spinal cord.