右美托咪定对家兔结肠平滑肌自发收缩功能的影响：离体实验  

Effect of dexmedetomidine on spontaneous contraction of colon smooth muscles of rabbits in vitro

作　　者：申军梅[1] 苗穗兵[2] 李旭懿 崔芳华[3] 李煜[4] 李楠[3] 刘宸光 靳睿哲 关玥[3] 

机构地区：[1]河北医科大学第四医院麻醉科,石家庄市050011 [2]河北医科大学生化教研室,石家庄市050017 [3]河北医科大学生理教研室,石家庄市050017 [4]河北医科大学临床学院实验中心,石家庄市050017

出　　处：《中华麻醉学杂志》2016年第4期442-446,共5页Chinese Journal of Anesthesiology

基　　金：河北省重点研发计划自筹项目（152777225）;河北医科大学大学生创新性实验计划项目（USIP2016143）

摘　　要：目的探讨右美托咪定对家兔结肠平滑肌自发收缩功能的影响。方法健康家兔2～3月龄，体重1．8～2．3kg，雌雄不拘，处死后制备结肠段，于K—H液孵育稳定后（基础状态）进行药物处理。实验Ⅰ取6个结肠段，K—H液中累积法加入右美托咪定，使终浓度分别为1、10、20、40、60、80和100nmol／L；实验Ⅱ取6个结肠段，K—H液加入右美托咪定（终浓度60nmol／L）孵育3min，洗脱后加入左旋硝基精氨酸甲酯（终浓度100mmol／L），孵育10rain后再次加入右美托咪定（终浓度60nmol／L）；实验Ⅲ取12个结肠段，采用随机数字表法分为2组（n=6）：CaCl2组和右美托咪定＋CaCI：组。CaCl2组更换为无钙K—H液，5min后加入CaCl2（终浓度1．8mol／L）；右美托咪定＋CaCl2组更换为无钙K—H液，孵育5min后加入右美托咪定（终浓度60nmol／L），孵育10min后加入CaCl2（终浓度1．8mol／L）；实验Ⅳ取12个结肠段，采用随机数字表法分为2组（n=6）：雷诺丁组和右美托咪定＋雷诺丁组。雷诺丁组更换为无钙K-H液，孵育5min后加入雷诺丁（终浓度0．2mmol／L）；右美托咪定＋雷诺丁组更换为无钙K—H液，孵育5min后加入右美托咪定（终浓度60nmol／L），孵育10min后加入雷诺丁（终浓度0．2mmol／L）。将结肠段与张力换能器相连，应用BL-420F生物信号采集处珲系统记录基础状态时和各处理措施孵育时结肠平滑肌收缩力度和频率。结果右美托咪定可降低家兔结肠平滑肌收缩力度，且呈剂量依赖性，对收缩频率无明显影响。单独应用左旋硝基精氨酸甲酯对结肠平滑肌收缩频率和力度无影响，但可减弱右美托咪定对结肠平滑肌收缩力度的抑制效虚。无钙K—H液孵育时结肠平滑肌收缩频率和力度明显降低，CaCl2和雷诺丁可提高结肠平滑肌收缩频率和力度；预先给予右美托咪定明显抑制CaCl2和雷诺丁提高结肠平�Objective To investigate the effect of dexmedetomidine on the spontaneous contraction of colon smooth muscles of rabbits. Methods Healthy rabbits of both sexes, aged 2-3 months, weighing 1.8-2.3 kg, were sacrificed to prepare colon smooth muscle specimens which were incubated with the K-H solution. Treatment with drugs was performed after incubation was stable （baseline）. Experiment I Six colon segments were selected, and dexmedetomidine was accumulatively added to the K-H solution with the final concentrations of 1, 10, 20, 40, 60 80 and 100 nmol/L in sequence. Experiment Ⅱ Six colon segments were selected, dexmedetomidine was added to the K-H solution （final concentration 60 nmol/L） , and the colon segments were incubated for 3 min followed by washout, NG-nitro-L-arginine methyl ester （final concentration 100 mmol/L） was then added to the K-H solution, the colon segments were then incubated for 10 min, and then dexmedetomidine （final concentration 60 nmol/L） was added again. Experiment 11/ Twelve colon segments were randomly divided into 2 groups （n= 6 each） using a random number table： CaCl2 group and dexmedetomidine＋ CaCl2 group, The culture medium was replaced with calcium- free K-H solution, and 5 rain later CaCl2 （final concentration 1.8mol/L） was added in CaCl2 group. The culture medium was replaced with calcium-free K-H solution, the colon segments were incubated for 5 min, dexmedetomidine （final concentration 60 mol/L） was added, the colon segments were then incubated for 10 min, and then CaCl2 （final concentration 1.8 tool/L） was added in dexmedetomidine＋ CaCl2 group, Experiment Ⅳ Twelve colon segments were randomly divided into 2 groups （n= 6 each） using a random number table： ryanodine group and dexmedetomidine＋ryanodine group. The culture medium was replaced with calcium-free K-H solution, the colon segments were incubated for 5 min, and then ryanodine （final concentration 0.2 mmol/L） was added in ryanodine group. The culture medium was replaced

关 键 词：右美托咪啶 结肠 平滑肌 肌收缩 

分 类 号：R614[医药卫生—麻醉学]