Deady J E, Koblin D D, Eger E I, Heavner J E, D'Aoust B
Anesth Analg. 1981 Jun;60(6):380-4.
Anesthetic potencies of nitrous oxide, isoflurane, enflurane, halothane, cyclopropane, or chloroform were measured in male (CD-1) mice using three end points: (a) the ability to maintain an upright position (the righting-response ED50, RR ED50); (b) the response to a tail-clamp stimulus (MAC); and (c) the response to heat applied to the tail (tail-flick ED50, TF ED50). The ratio of RR ED50 to MAC ranged from mean values of 0.475 for isoflurane, 0.507 for cyclopropane, 0.524 for enflurane, and less than 0.55 for N2O, to 0.600 for halothane and 0.621 for chloroform. The ratios of RR EDS50 to MAC for halothane differed significantly from the ratios for isoflurane and enflurane. The mean values for TF ED50/MAC and RR ED50/TG ED50 ranged from 0.688 to 1.01 and 0.664 to 0.682, respectively, for isoflurane, enflurane, and halothane. The nitrous oxide RR ED50/TF ED50, however, was 1.34. The ratios of TF ED50 to MAC were significantly different for halothane and isoflurane. The different end points were measured in an attempt to determine whether the response in mice anesthetized with a particular agent was the same with varying stimuli. The differences found suggest that a unitary mechanism of anesthetic action cannot completely explain the depression defined by these three end points.
采用三个终点指标，在雄性（CD-1）小鼠中测定了氧化亚氮、异氟烷、恩氟烷、氟烷、环丙烷或氯仿的麻醉效能：（a）维持直立姿势的能力（翻正反射半数有效剂量，RR ED50）；（b）对夹尾刺激的反应（最低肺泡有效浓度，MAC）；（c）对尾巴施加热量的反应（甩尾半数有效剂量，TF ED50）。RR ED50与MAC的比值范围为：异氟烷平均值为0.475，环丙烷为0.507，恩氟烷为0.524，N2O小于0.55，氟烷为0.600，氯仿为0.621。氟烷的RR EDS50与MAC的比值与异氟烷和恩氟烷的比值有显著差异。对于异氟烷、恩氟烷和氟烷，TF ED50/MAC和RR ED50/TG ED50的平均值分别为0.688至1.01和0.664至0.682。然而，氧化亚氮的RR ED50/TF ED50为1.34。氟烷和异氟烷的TF ED50与MAC的比值有显著差异。测量不同的终点指标旨在确定用特定药物麻醉的小鼠对不同刺激的反应是否相同。所发现的差异表明，单一的麻醉作用机制不能完全解释由这三个终点指标所定义的抑制作用。
