The efects of intrathecal administration of cyclin-dependent kinase 5 inhibitor roscovitine on the pain behavior of CCD rats

Objective To study the effects of intrathecal injeetion of cyclin-dependent kinase 5 inhibitor Roseovitine on the pain behavior in chronic compression of dosal root ganglia(CCD)rats.Methods 24 male SD rats with intrathecal catheter properly inserted,were randomly divided into four groups(n=6):sham operation group(S group),50%DMSO was used as the vehicle control for the intrathecal injection;CCD group treated with 50%DMSO(operated for chronic compression of right dorsal root ganglion,C group);Roscovitine group(Roscovitine 50μg,R group)and CCD0 group was not injected any drugs(C0 group),just as that in control.To evaluate the behaviorsl changes,paw withdrawal mechanical threshold(PWMT)and paw withdrawal thermal latency (PWTL)were measured 0,7 days and 1,4,8 h after injection on the 7th day of CCD.Results Compared with the value-based,with the exception of S group,all of the rats after CCD PWMT and PWTL were significantly lower(P＜0.05).PWMT of R group was no significant change at all times point.Compared to value-based PWTL of R group was a marked increase.and remained at a relatively high level(P＜0.05).Conclusion Cdk5 involves in spinal dorsal horn of neuropathic pain signal transduction process. Key words: Neuropathic pain; Cyclin-dependent kinase 5; Spinal dorsal horn