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

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.