Aim To investigate the role of spinal con-nexin 43 ( Cx43 ) in the development of chronic morphine antinociceptive tolerance and whether the c-Jun N-terminal kinase ( JNK ) pathway was involved in this role. Methods Morphine 10 μl ( 1. 5 g · L-1) was adminitered intrathecally for consecutive 7 days to establish the model of chronic analgesic tolerance to morphine in the adult ♂ Sprague-Dawley rats. Hot radiation tail flick test was used to assess the analgesic efficacy. Western blot assay was applied to detect the expressions of Cx43, phosphorylated ( p )-JNK, total (t )-JNK, p-c-Jun and t-c-Jun. Results On the 7th day of repeated intrathecal injection of morphine, the expression of Cx43 was remarkably increased in the lumbar spinal cord. Coadministration of Gap26 ( a specific inhibitor of Cx43, 1. 5 g · L-1, 10 μ1 ) with morphine obviously attenuated not only morphine antinociceptive tolerance, but also the activiation of the JNK and c-Jun induced by chronic morphine treatment. Conclusion The spinal Cx43 mediates morphine antinociceptive tolerance through JNK pathway in rats.
国家科技期刊平台
NSTL
万方数据
维普
