三叉神经痛大鼠模型中Cdk5/p35的表达与活性

Expression and activity of Cdk5/p35 in a rat model of trigeminal neuropathic pain

目的:探讨Cdk5激活剂p35在三叉神经痛过程中所起的作用。方法:以三叉神经眶下支(ION)的慢性压迫性损伤(CCI)建立的三叉神经痛大鼠模型为研究对象,采用Western印迹、免疫沉降和Cdk5活性分析方法,检测大鼠眶下神经慢性压迫性损伤(CCI-ION)后三叉神经脊束尾核(Vc)组织中Cdk5的活性变化和Cdk5、p35的表达水平。应用SPSS13.0软件包中的两两比较和扩展t检验进行统计学分析。结果:CCI-ION呈时间依赖形式诱导神经损伤侧Vc组织中的p35上调(第1天为1.23±0.15,第3天为1.36±0.12,第7天为1.62±0.17,第14天为1.83±0.16);Cdk5表达在CCI-ION第1天到第14天基本一致,而Cdk5的活性与p35表达具有一致性;CCI-ION第14天,Vc内的Cdk5活性(115.5Kcpm)是CCI-ION第1天Vc内的Cdk5活性(19.0Kcpm)的6倍,各组之间均有显著差异(P<0.01)。结论:Cdk5/p35与三叉神经痛过程中神经元突触变化及神经元可塑性有密切关系。

PURPOSE：To test the hypothesis that Cdk5/p35 plays important roles during trigeminal neuropathic pain.METHODS：Trigeminal neuralgia rat model was established with a chronic constriction injury （CCI） of the infraorbital branch of the trigeminal nerve （ION）.The change of Cdk5 activity, expression of Cdk5 and p35 in Vc after CCI-ION were studied by Western blot, immunoprecipitation and Kinase assay.Statistical analysis was performed using SPSS13.0 software package.RESULTS：Western blot showed CCI-ION induced a time-dependent upregulation of p35 primarily within the ipsilateral superficial laminae of Vc （day 1：1.23±0.15, day 3：1.36±0.12, day 7：1.62±0.17, day 14：1.83±0.16）.In contrast, the expression of Cdk5 was constant during day 1-14 in Vc after CCI-ION.Cdk5 activity on day 14 in Vc after CCI-ION （115.5 Kcpm） was 6 times as that on day 1 in Vc after CCI-ION （19.0 Kcpm）.The difference was significant （P〈0.01）.CONCLUSIONS：The results suggest that cdk5/p35 may plays important roles on synaptic reorganization of Vc after CCI-ION, expression of p35 may be a novel regulatory mechanism to control cdk5 activity in Vc after CCI-ION.