摘要
目的 观测单独或联合应用氯胺酮和镁在重组NMDA受体中的作用及相互影响。方法 应用电压钳测试和记录受体的反应电流 ,所测试的受体为表达于蛙卵细胞上的NR1/NR2A和NR1/NR2B受体。支持电压为 70mV ,以谷氨酸和甘氨酸作为受体激动剂 ,分别测试单独和联合应用s(+) 氯胺酮和镁时反应电流的情况。结果 单独应用镁和氯胺酮均对NMDA受体产生非竞争性抑制作用。镁在NR1/NR2A和NR1/NR2B中的IC5 0分别为 (4 2± 1 2 )× 10 -4mol和 (6 3± 2 4 )× 10 -4mol/L ,两组无差别 ;s(+) 氯胺酮在NR1/NR2A和NR1/NR2B中的IC5 0分别为 (4 1± 2 5 )× 10 -6mol/L和 (3 0± 0 3)× 10 -6mol/L ,两组亦无差别。当联合应用镁和氯胺酮时二者的IC5 0在NR1/NR2A和NR1/NR2B中均减少了 90 %以上 ,显示二者有显著的协同作用。结论 镁和氯胺酮均对NMDA受体产生非竞争性抑制作用 。
Objective It has been shown that ketamine and magnesium used in combination provide more effective analgesia than either drug alone The purpose of this study was to investigate the effects and interaction of the two drugs on recombinantly expressed NMDA receptors Methods Xenopus oocytes expressing NR1/NR2A or NR1/NR2B glutamate receptors were stimulated with glutamate/glycine and studied at a holding potential of 70mV using two electrode voltage clamp The effects of magnesium and s(+) ketamine alone or in combination on NMDA signaling were determined Results Magnesium and s(+) ketamine alone inhibited NMDA receptors non competitively IC50s of magnesium were (4 2±1 2) ×10 -4 mol/L and (6 3±2 4) ×10 -4 mol/L on NR1/NR2A and NR1/NR2B, while IC50s of s(+) ketamine on NR1/NR2A and NR1/NR2B were (4 1±2 5) ×10 -6 mol/L and (3 0±0 3) ×10 -6 mol/L respectively Magnesium and s(+) ketamine used in combination decreased IC50s more than 90% at both receptors Isobolographic analysis demonstrated superadditive interactions Conclusions s(+) ketamine and magnesium inhibit responses of recombinantly expressed NMDA recptors non competitively, and the combinations of the two drugs produces a synergistic effect
出处
《中华麻醉学杂志》
CAS
CSCD
北大核心
2001年第5期295-298,共4页
Chinese Journal of Anesthesiology
