ABSTRACT
Objective To explore the role of spinal cord p300 in neuropathic pain induced by chronic constriction nerve injury (CCI) in rats.Methods Thirty two Sprague-Dawley (SD) rats were randomly divided into sham and CCI groups,14 days after surgery,immuno-fluorescence staining and Western blot were used to detect distribution and expression of p300 protein.After rats were successfully implanted with an intrathecal catheter and accepted CCI surgery,another 24 rats were randomly divided into three groups (n =8):dimethyl sulfoxide (DMSO) group,p300 acetyltransferase inhibitor C646 group,and control C37 group.Each rat were administered through the intrathecal catheter from day 7 to 14 and mechanical withdraw threshold were tested.Results (1) The p300 positive cells were detected mainly in neurons,and p300 protein in spinal cord of CCI group were significantly higher than sham group (P ＜0.05).(2) C646 alleviated significantly neuropathic pain in rats,without significant changes in pain threshold after injection of C37 and DMSO.Conclusions The p300 protein in spinal cord was involved in the development of neuropathic pain in rats,the mechanism may be referred to its acetyltransferase activity.
ABSTRACT
Objective To investigate the effect of intrathecal injection of lentiviral vector-mediated up-regulation of glial cell line-derived neurotrophicfactor (GDNF) on neuropathic pain of chronic constriction injury (CCI) rats.Methods The CCI model was prepared by ligating the sciatic nerve of Sprague-Dawley (SD) rats.Seven days after CCI modeling,a single intrathecal injection of lentiviral vectors (LV)-GDNF was given.Before CCI and 3,5,7,14,and 21 days after CCI modeling,the mechanical pain threshold was tested in rats,and 21 days after surgery,Western blot was used to detect the expression of GDNF protein.Results On 21 days after CCI modeling,GDNF expression was reduced compared to sham group.After intrathecal injection of LV-GDNF,GDNF expression was up-regulated in the spinal cord,and CCI-induced mechanical hyperalgesia in rats was alleviated.Conclusions Intrathecal injection LV-GDNF can up-regulate the expression of GDNF and alleviate neuropathic pain in CCI rats.