CAJ | 학술논문

目的评价多次腹腔注射右美托咪定对慢性脑缺血大鼠认知功能的影响.方法健康雄性SD大鼠48只,3～4月龄,体重250 ～ 300 g,采用随机数字表法,将其随机分为4组(n=12)∶假手术组(S组)、慢性脑缺血组(IS组)、右美托咪定治疗1组(DXM1组)和右美托咪定治疗2组(DXM2组).IS组、DXM1组和DXM2组采用永久结扎双侧颈总动脉法制备大鼠慢性前脑缺血模型.DXM1组于双侧颈总动脉结扎前30 min、结扎后3、12、24和48 h时腹腔注射右美托咪定5 μg/kg,DXM2组结扎后3、12、24和48 h时腹腔注射右美托咪定5μg/kg.结扎后2周时进行Morris水迷宫实验,随后处死大鼠取海马,TUNEL法检测神经元凋亡情况,计算神经元凋亡率,Western blot法检测海马Bcl-2表达.结果与S组比较,IS组于定位航行实验第2天至第5天、DXM1组和DXM2组于实验第2天逃避潜伏期延长,IS组、DXM1组和DXM2组第1象限停留时间缩短,细胞凋亡率增加,Bcl-2表达上调(P＜0.05)；与IS组比较,DXM1组和DXM2组于定位航行实验第3天至第5天逃避潜伏期缩短,第1象限停留时间延长,细胞凋亡率降低,Bcl-2表达上调(P＜0.05)；DXM1组与DXM2组间比较上述各指标差异无统计学意义(P＞0.05).结论多次腹腔注射右美托咪定可改善慢性脑缺血大鼠认知功能,其机制可能与抑制海马神经元凋亡有关.
목적 평개다차복강주사우미탁미정대만성뇌결혈대서인지공능적영향.방법 건강웅성SD대서48지,3～4월령,체중250 ～ 300 g,채용수궤수자표법,장기수궤분위4조(n=12)∶가수술조(S조)、만성뇌결혈조(IS조)、우미탁미정치료1조(DXM1조)화우미탁미정치료2조(DXM2조).IS조、DXM1조화DXM2조채용영구결찰쌍측경총동맥법제비대서만성전뇌결혈모형.DXM1조우쌍측경총동맥결찰전30 min、결찰후3、12、24화48 h시복강주사우미탁미정5 μg/kg,DXM2조결찰후3、12、24화48 h시복강주사우미탁미정5μg/kg.결찰후2주시진행Morris수미궁실험,수후처사대서취해마,TUNEL법검측신경원조망정황,계산신경원조망솔,Western blot법검측해마Bcl-2표체.결과 여S조비교,IS조우정위항행실험제2천지제5천、DXM1조화DXM2조우실험제2천도피잠복기연장,IS조、DXM1조화DXM2조제1상한정류시간축단,세포조망솔증가,Bcl-2표체상조(P＜0.05)；여IS조비교,DXM1조화DXM2조우정위항행실험제3천지제5천도피잠복기축단,제1상한정류시간연장,세포조망솔강저,Bcl-2표체상조(P＜0.05)；DXM1조여DXM2조간비교상술각지표차이무통계학의의(P＞0.05).결론 다차복강주사우미탁미정가개선만성뇌결혈대서인지공능,기궤제가능여억제해마신경원조망유관.
Objective To investigate the effects of repeated intraperitoneal dexmedetomidine on the cognitive function in rats with chronic cerebral ischemia.Methods Forty-eight male Sprague-Dawley rats,aged 3-4months,weighing 250-300 g,were randomly divided into 4 groups (n =12 each) ∶ sham operation group (group S),chronic cerebral ischemia group (group IS),dexmedetomidine treatment 1 group (group DXM1) and dexmedetomidine treatment 2 group (group DXM2).Dexmedetomidine 5 μg/kg was injected intraperitoneally at 30 min before occlusion of bilateral common carotid arteries and 3,12,24 and 48 h after occlusion in group DXM1,and at 3,12,24 and 48 h after occlusion in group DXM2.The cognitive function was assessed by Morris water maze 2 weeks after occlusion.The apoptosis was examined by TUNEL.The expression of Bcl-2 protein in hippocampus was detected by Western blot.Results Compared with group S,the escape latency was significantly prolonged from 2nd day to 5th day after the place navigation test in group IS and on 2nd day after Morris water maze test in groups DXM1 and DXM2,and the time of staying in 1 st quadrant was significantly shortened,the apoptotic rate was increased,and the expression of Bcl-2 was up-regulated in groups IS,DXM1 and DXM2 (P ＜ 0.05).Compared with group IS,the escape latency was significantly shortened from 3rd day to 5th day after the place navigation