维生素B12对大鼠坐骨神经结扎神经痛的影响及血药浓度监测

EFFECTS OF VITAMINE B12 ON THE NEUROPATHIC PAIN IN RATS WITH LIGATION OF SCIATIC NERVE AND THE MEASUREMENT OF SERUM VITAMINE B12 CONCENTRA-TION

摘要:

目的:观察维生素B12(VitB12)对大鼠坐骨神经结扎神经病理痛的影响并监测其血药浓度。方法:采用坐骨神经慢性结扎损伤(CCI)模型,32只SD大鼠,随机分为4组(n=8)。对照组(Con组):不接受任何手术操作;假手术组(Sham组):只分离坐骨神经;CCI组:结扎坐骨神经;CCI VitB12组:坐骨神经结扎术后腹腔注射VitB120.5mg/kg/d两周。于术前2天,术后1、3、5、7、10、14天测定各组大鼠热缩足反射潜伏期(TWL)、机械缩足反射阈值(MWT),并于术后3?7?14天测定各组大鼠血清VitB12浓度。结果:与Sham组比较,CCI组术后各天TWL?MWT明显降低(P<0.01);与CCI组比较,CCI VitB12组术后1、3、10、14天TWL明显增高(P<0.01),而术后各天MWT无明显差别。Sham组术后3、7、14天血清VitB12浓度与Con组无差别(P>0.05);CCI组术后3天血清VitB12浓度低于Sham组、Con组(P<0.05)、CCI VitB12组(P<0.01)以及CCI组术后14天(P<0.05);CCI VitB12组术后7天?14天血清VitB12浓度均高于Con组、Sham组和CCI组(P<0.01)。结论:VitB12减轻CCI大鼠热痛觉过敏,但对机械痛觉过敏无影响;CCI大鼠神经损伤早期血清VitB浓度降低。

Abstract:

Objective:To investigate the effect of vitamine B12(VitB12) on neuropathic pain in rats and measure the serumal Vit B12 concentrations.Methods:Thirty two male SD rats were randomly divided into 4 groups:Control group(Con),Sham operation group(Sham),Chronic constriction injury group(CCI)and VitB12 treated group(CCI VitB12).CCI model was adopted,thermal withdrawal latency(TWL) and mechanical withdrawal threshold(MWT) of rats were measured at 1st,2nd day pre-operation and 1st,3th,5th,7th,10th,14th day post-operation.Serumal VitB12 concentration of rats were measured at 3rd,7th,14th day post-operation.Results:TWL and MWT in CCI group were significantly lower than those in Sham group at 3rd post-operation day(P<0.01);TWL in group CCI VitB12 was higher than that in CCI group at 1st,3rd,10th,14th day post-operation,there was no significant difference in MWT between the two groups.There was no difference in serumal VitB12 concentration between Sham and Congroups(P>0.05);serumal VitB12 concentration in CCI group was lower at 3rd day post-operation than that in CCI group at 14th day post-operation(P<0.05),serumal VitB12 concentration in CCI group was lower than that in Sham,Con(P<0.05),CCI VitB12 groups(P<0.01);Serumal VitB12 concentration in CCI VitB12 group at 7th,14th day post-operation was significantly higher than that in Con,Sham and CCI groups(P<0.01).Conclusion:VitB12 can alleviate thermal hyperalgesia induced by CCI,but not the mechanical hyperalgesia;Serumal VitB12 concentration decreases in the early stage of nerve injury in CCI rats.