置丰富环境中饲养的三叉神经病理痛小鼠行为学、脑组织终板床核活动度观察

Effects of enriched environment on behavior improvement and activity of BNST in brain tissues of mice with trigeminal neuropathic pain

目的观察置于丰富环境中饲养的三叉神经病理痛小鼠行为学的改善情况,及脑组织终板核活动度。方法C57/BL6小鼠8周,随机分为丰富环境组、标准环境组、假手术组(Sham组)。丰富环境组小鼠三叉神经病理痛造模后放于丰富环境箱内培养,标准环境组小鼠三叉神经病理痛造模后放于正常鼠笼中培养,假手术组仅将小鼠口腔内黏膜划破后放于正常鼠笼中培养,均培养35 d。术后35 d,每组进行面部机械痛测试(von-frey),矿场(OF)、高架十字迷宫(EPM),悬尾(TS)等行为测试,采用免疫组织化学染色法检测终纹床核delta FosB。结果与Sham组相比,标准环境组出现明显的痛敏化(P<0.05),OF中心区停留时间缩短(P<0.05),EPM开臂停留时间缩短(P<0.05),穿梭开臂次数减少(P<0.05),TS不动时间延长(P<0.05),出现焦虑抑郁样行为。与标准环境组相比,丰富环境组三叉神经病理痛有所缓解(P<0.05),OF、EPM中无焦虑表现(P>0.05),TS中不动时间缩短(P<0.05),抑郁行为改善。与Sham组比较,标准环境组终纹床核处delta FosB细胞数增加(P<0.01);与标准环境组比较,丰富环境组终纹床核处delta FosB细胞数减少(P<0.05)。结论置于丰富环境中饲养的三叉神经病理痛小鼠眶下神经卡压诱发的痛敏化和焦虑抑郁样行为明显改善,脑组织终板核活动度降低。

Objective To observe the effect of enriched environment(EE)on behavior improvement in mice with trigeminal neuropathic pain(TN)and activity of the bed nuclei of the stria terminalis(BNST)in the brain tissues.Meth⁃ods C57/BL6 mice at the age of eight weeks were randomized into three groups:the sham group(n=6),infarorbital nerve constriction+standard environment group(CION+SE group,n=9),and infarorbital nerve constriction+enriched environment group(CION+EE group,n=8).In the sham group,we slightly cut the oral mocosa of mice and then put them back to the normal mice cage.In the CION+SE group,the mice were put back to the normal mice cage.after CION surgery In the CION+EE group,after the surgery,the mice were quickly put into the enriched environmental cage.After 35-day intervention,the behavior tests were conducted,including von-frey,open field(OF)test,elevated plus maze(EPM)test,and tail suspension(TS)test,etc.Then,immunohistochemical staining was used to detect the delta FosB cells in the BNST.Results Compared with the sham group,the CION+SE group appeared obviously pain sensitivity(P<0.05),the duration of stay in the OF decreased(P<0.05),open-arm time reduced in EPM(P<0.05),open-arm entries decreased(P<0.05),and immobile duration of TS increased(P<0.05).The mice in the CION+SE group displayed anxio-depression.Compared with the CION+SE group,the mice were relieved from TN,and did not display anxio-depres⁃sion in OF and EPM(P>0.05),the duration of stay in the TS decreased(P<0.05),and the depressive behavior of the mice decreased in the CION+EE group.Compared with the sham group,the number of delta FosB cells in the BNST in⁃creased in the CION+SE group(P<0.01);compared with the CION+SE group,the number of delta FosB cells in the BNST decreased in the CION+EE group(P<0.05)Conclusion Enriched environment can allieviate pain sensitivity and anxio-depressive behaviors of mice with TN,which might inhibit the activity of BNST of brain tissues.