Comparison of the behavioral effects of parecoxib pretreatment on the rats with neuropathic pain by different administration pathways

YANG Yang; TU Wei-feng; DENG Li-zhen; RAO Yun; HUANG Xi-zhao; LU Jian-hua

Abstract：Objective To compare the behavioral effects of parecoxib pretreatment on the rats with Neuropathic pain by different administration pathways , including intrathecal and intraperitoneal injection and perineural infiltration . Methods Thirty adult male rats were randomly divided into five groups: SC controlled group ( Group SC ) , L5 spinal nerve ligation group (Group SNL), parecoxib intrathecal injection group (Group IT), parecoxib intraperitoneal injection group (Group IP), perineural parecoxib infiltration group (Group PI).Rats in treatment groups were given with parecoxib pretreatment.Fifty percent paw mechanical withdrawal threshold (50%PMWT) and paw thermal withdrawal latency (PT-WL) were measured on the 1st pre-operative and 3rd, 7th, 10th, 14th, 21st post-operative day.Results The post-op-erative left 50%PMWT in Group SNL and the three treatment groups were significantly lower than those in Group SC ( P<0.05);meanwhile, the post-operative left 50%PMWT in the three treatment groups were significantly higher than those in Group SNL (P<0.05).The post-operative left 50%PMWT in Group IT were significantly higher than those in Group IP and Group PI ( P<0.05 ) , and there were no difference between left 50%PMWT in Group IP and Group PI ( P>0.05).Compared with Group SC, noticed reduced right 50%PMWT in the other four group were also observed , which was partially inhibited by intrathecal pretreatment of parecoxib .Conclusion All of the parecoxib pretreatment by three different administration pathways can alleviate the mechanical and thermal pain after spinal nerve ligation in rats .Intrathe-cal administration provides the best efficacy , while the other two administration pathways provides similar results .