Effects of vitamin C combined with low dose of gabapentin on neuropathic pain in rats
10.3760/cma.j.issn.0254-1416.2014.04.011
- VernacularTitle:维生素C复合低剂量加巴喷丁对大鼠神经病理性痛的影响
- Author:
Rui LI
;
Le SHEN
;
Xuerong YU
;
Wei LIU
;
Yuguang HUANG
- Publication Type:Journal Article
- Keywords:
Neuralgia;
Ascorbic acid;
Gabapentin
- From:
Chinese Journal of Anesthesiology
2014;34(4):419-422
- CountryChina
- Language:Chinese
-
Abstract:
Objective To evaluate the effects of vitamin C combined with low dose of gabapentin on neuropathic pain (NP) in rats.Methods Fifty male Sprague-Dawley rats,weighing 225-275 g,aged 6-7 weeks,were randomly assigned into 5 groups (n =10 each):sham operation group (group Sham),NP group,vitamin C group (group VitC),gabapentin group (group Gap),and vitamin C combined with gabapentin group (VitC + Gap group).NP was induced by chronic constrictive injury in the rats anesthetized with pentobarbital sodium.The sciatic nerve was exposed and 4 silk ligatures were placed on the sciatic nerve at 1 mm intervals.In VitC,Gap and VitC+ Gap groups,vitamin C 500 mg/kg,gabapentin 30 mg/kg,and vitamin C 500 mg/kg + gabapentin 30 mg/kg diluted in normal saline 1 ml were injected intraperitoneally,respectively,twice a day for 7 consecutive days starting from 7 days after NP.Normal saline 1 ml was given in Sham and NP groups.Before NP and at 3,7,and 14 days after NP,the paw withdrawal threshold to mechanical stimuli (PWMT) and paw withdrawal latency to thermal stimuli (PWTL) were measured.At 14 days after NP,the blood samples were drawn from the carotid arteries.The rats were then sacrificed and the spinal cord was removed for determination of concentrations of malondialdehyde (MDA) in serum (by using Thiobarbituric acid method) and Slc23a2 mRNA expression (by RTPCR).Results Compared with Sham group,PWMT and PWTL in left paws were significantly decreased in NP,VitC,Gap ard VitC + Gap groups,the concentrations of MDA in serum were increased and Slc23a2 mRNA expression was down-regulated in NP group,Slc23a2 mRNA expression was down-regulated in VitC and Gap groups,and no significant change in Slc23a2 mRNA expression was found in VitC + Gap group.Compared with NP group,PWMT and PWTL in left paws were significantly increased,the concentrations of MDA in serum were decreased,and Slc23a2 mRNA expression was up-regulated in VitC + Gap group,the concentrations of MDA in serum were decreased in VitC group,and no significant changes were found in PWMT and PWTL in left paws in VitC and Gap groups.There were no significant differences in PWMT and PWTL in fight paws at each time point between the five groups.Conclusion Vitamin C combined with low dose of gabapentin can relieve NP effectively,and up-regulation of Slc23a2 mRNA expression,increased trafficking of vitamin C to neurons and inhibition of oxidative stress may be involved in the mechanism.