右美托咪定抑制Ca^(2+)超载保护大鼠脊髓缺血再灌注损伤  

Dexmedetomidine protects spinal cord ischemia-reperfusion injury in rats by inhibiting Ca^(2+)overload

作　　者：姜胜 杨少青 王雨欣 宋泉江 周彬 邵春艳 王晓杜 宋厚辉 JIANG Sheng;YANG Shaoqing;WANG Yuxin;SONG Quanjiang;ZHOU Bin;SHAO Chunyan;WANG Xiaodu;SONG Houhui(Key Laboratory of Applied Technology on Green-Eco-Healthy Animal Husbandry of Zhejiang Province,Zhejiang Provincial Engineering Laboratory for Animal Health Inspection&Internet Technology,Zhejiang International Science and Technology Cooperation Base for Veterinary Medicine and Health Management,China-Australia Joint Laboratory for Animal Health Big Data Analytics,College of Animal Science and Technology,College of Veterinary Medicine of Zhejiang A&F University,Hangzhou 311300,China)

机构地区：[1]浙江农林大学动物科技学院/动物医学院,浙江省畜禽绿色生态健康养殖应用技术研究重点实验室/动物健康互联网检测技术浙江省工程实验室/动物医学与健康管理浙江省国际科技合作基地/中澳动物健康大数据分析联合实验室,浙江杭州311300

出　　处：《中国兽医学报》2022年第8期1660-1668,共9页Chinese Journal of Veterinary Science

基　　金：国家自然科学基金资助项目(31602119,31802258);浙江省自然科学基金资助项目(LQ20C180002);浙江农林大学科研启动基金资助项目(2015FR042,2018FR009,2018FR015)。

摘　　要：为了探讨右美托咪定(dexmedetomidine,Dex)对大鼠脊髓缺血再灌注(ischemia-reperfusion,I/R)损伤的保护作用及机制,通过改良Zivin法夹闭肠系膜上动脉及右肾动脉之间的腹主动脉50 min建立大鼠脊髓I/R模型。I/R前通过尾静脉进行Dex预处理,通过腹腔注射进行NPS2143和KN93预处理。采用BBB评分和HE染色评估脊髓损伤,微板法检测钙离子浓度,Western blot和荧光定量PCR分别分析CaSR和CaMKⅡ蛋白表达和mRNA转录水平分析。结果显示,与假手术组(Sham)比较,I/R 24 h、Dex 24 h、NPS2143+I/R 24 h及KN93+I/R 24 h组大鼠BBB评分均显著降低(P<0.01),I/R 48 h和KN93+I/R 48 h组BBB评分显著降低(P<0.01);与I/R组比较,Dex组大鼠BBB评分显著升高(P<0.01)。I/R 24 h与I/R 48 h组HE染色结果显示,脊髓神经元胞体固缩,胞核结构不清,染色加深,甚至消失,胶质细胞增生,提示脊髓损伤严重,而Sham组神经元未见明显异常,与I/R组比较,HE结果提示Dex组脊髓组织损伤程度轻微。与Sham组比较,I/R 24 h和I/R 48 h组脊髓钙离子浓度显著升高(P<0.01);与I/R 24 h组比较,Dex 24 h组脊髓钙离子浓度显著降低(P<0.01)。与Sham 24 h组比较,I/R 24 h组大鼠脊髓CaSR和CAMKⅡ的蛋白与mRNA表达水平显著升高(P<0.01);Dex 24 h组大鼠脊髓组织CaSR与CAMKⅡ的mRNA和蛋白的表达水平显著降低(P<0.01)。结果表明Dex可下调CaSR和CAMKII的mRNA与蛋白表达水平,减轻钙超载,从而保护脊髓缺血再灌注损伤。该研究为Dexm减轻脊髓I/R损伤的临床应用提供了理论依据。To investigate the protective effect and mechanism of dexmedetomidine(Dex)on spinal cord ischemia-reperfusion(I/R)injury in rats.The spinal cord I/R model was established by clamping the abdominal aorta between the superior mesenteric artery and the right renal artery for 50 min.Before I/R,Dex were administrated through the caudal vein,NPS2143 and KN93 were injected intraperitoneally.Spinal cord injury was evaluated by BBB score and HE staining.Calcium concentration was detected by microplate method.CaSR and CaMKⅡprotein expression and mRNA tran scription were respectively analyzed by Western blot and fluorescence quantitative PCR.Results showed that compared with sham,the BBB scores of I/R 24h,Dex 24h,NPS2143+I/R 24hand KN93+I/R 24h groups decreased significantly(P<0.01),and the BBB scores of I/R 48h group and KN93+I/R 48h group increased significantly(P<0.01).Compared with I/R group,the BBB score of Dex group increased significantly(P<0.01).The HE staining results of I/R 24h and I/R 48h groups showed that the cell bodies of spinal cord neurons were pyknosis,the nuclear structure was unclear,the staining deepened or even disappeared,and glial cells proliferated,these results suggested that the spinal cord injury was serious,while the neurons in sham group had no obvious abnormalities.Compared with I/R group,the results of HE staining showed that the degree of spinal cord injury in Dex group was slight.Compared with sham group,the concentration of calcium ion in spinal cord increased significantly in I/R 24h group and I/R 48h group(P<0.01);compared with the I/R 24h group,the spinal cord calcium concentration in Dex24h group decreased significantly(P<0.01).Compared with sham 24h group,the protein and mRNA expression levels of CaSR and CaMKⅡin I/R 24h group increased significantly(P<0.01),while the mRNA and protein expression levels of CaSR and CAMKⅡof spinal cord in Dex24h group decreased significantly(P<0.01).Dex can down-regulate the mRNA and protein expression levels of CaSR and CaMKⅡ,reduce calcium ove

关 键 词：右美托咪定 脊髓缺血再灌注 CASR CAMKⅡ 

分 类 号：S852.3[农业科学—基础兽医学]