Wood R W, Warren P H, Weiss B
J Pharmacol Exp Ther. 1980 Apr;213(1):128-32.
The analgesic properties of nitrous oxide (N2O) were evaluated with a fractional escape procedure ("shock titration" schedule). Shock intensity rose by a small step every few seconds. Each designated response by a rat or squirrel monkey subject reduced the amplitude of the shock by one step. Both species maintained stable tolerated levels of shock when exposed to pure oxygen or to air. Exposure to N2O yielded an elevation in maintained shock level whose magnitude depended on concentration. Statistically significant rises generally were apparent at N2O concentrations of 30 to 70%, which also tended to reduce shock level fluctuations. Since the raised shock levels were not accompanied by changes in overall response rate, they can be attributed to the analgesic properties of N2O.
采用分数逃逸程序（“冲击滴定”方案）评估了一氧化二氮（N2O）的镇痛特性。每隔几秒，电击强度就会小幅上升。大鼠或松鼠猴受试者的每次指定反应会使电击幅度降低一级。当暴露于纯氧或空气中时，这两个物种都能维持稳定的可耐受电击水平。暴露于N2O会使维持的电击水平升高，其幅度取决于浓度。在N2O浓度为30%至70%时，通常会出现统计学上显著的升高，这也往往会减少电击水平的波动。由于升高的电击水平并未伴随着总体反应率的变化，因此可将其归因于N2O的镇痛特性。
