Russell G B, Graybeal J M
Department of Anesthesia, Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, Hershey 7033, USA.
Pharmacology. 1995 Mar;50(3):162-7. doi: 10.1159/000139278.
The mechanisms of action of halogenated (isoflurane) and inorganic (nitrous oxide (N2O)) anesthetic gases are postulated to differ. We tested the null hypothesis that there is no difference in anesthetic potency, as determined by MAC (the minimum alveolar anesthetic concentration preventing purposeful movement to supramaximal noxious stimulation in 50% of animals) between the Long-Evans (LE) and Sprague-Dawley (SD) rat strains for isoflurane and N2O. MAC values were determined using a 45-second standard supramaximal electrical stimulation. MAC of isoflurane for SD rats was 1.28 +/- 0.20 vol% (mean +/- standard deviation), but 0.98 +/- 0.14 vol% for LE rats (p = 0.001). MAC values for N2O were the same: 1.53 +/- 0.1 and 1.58 +/- 0.14 ata for SD and LE rats, respectively. The interstrain MAC difference for isoflurane, but not N2O, suggests different mechanisms of action for the two agents.
卤化（异氟烷）和无机（一氧化二氮（N2O））麻醉气体的作用机制被认为有所不同。我们检验了无效假设，即对于异氟烷和N2O，在长 Evans（LE）和斯普拉格-道利（SD）大鼠品系之间，由MAC（在50%的动物中防止对超最大有害刺激产生有目的运动的最低肺泡麻醉浓度）所确定的麻醉效能没有差异。使用45秒的标准超最大电刺激来确定MAC值。SD大鼠异氟烷的MAC为1.28 +/- 0.20体积%（平均值 +/- 标准差），而LE大鼠为0.98 +/- 0.14体积%（p = 0.001）。N2O的MAC值相同：SD和LE大鼠分别为1.53 +/- 0.1和1.58 +/- 0.14绝对大气压。异氟烷存在品系间MAC差异，而N2O不存在，这表明这两种药物的作用机制不同。
