Tallarida R J, Kramer M S, Roy J W, Kester R A, Murray R B, Adler M W
J Pharmacol Exp Ther. 1977 Jun;201(3):587-92.
In the unanesthetized rabbit, morphine (12-16 mg/kg i.v.) produced a miosis that was not sustained. The response to the narcotic was a pupillary constriction that became maximal within 2 minutes following i.v. administration, after which time the pupil size fluctuated appreciably. The magnitude of the fluctuation, typically as high as 40% of control diameter, was much larger than can be attributed to "noise." The fluctuations occurred within a frequency of approximately 0.5 to 2/min. The miosis and subsequent fluctuation seen with 12 and 16 mg/kg of morphine was blocked by naloxone (0.5 mg/kg i.v.), but 128 mg/kg of morphine overcame the block. Cumulative dose-response curves for morphine and for morphine after naloxone yielded the value pA2=6.8 which is in agreement with the values obtained using other effects and species. Administration of morphine after exposure to high intensity light produced less miosis than that seen under normal illumination.
在未麻醉的兔子中，静脉注射吗啡（12 - 16毫克/千克）会产生一种不能持续的瞳孔缩小。对这种麻醉剂的反应是瞳孔收缩，静脉注射后2分钟内达到最大程度，此后瞳孔大小明显波动。波动幅度通常高达对照直径的40%，远大于可归因于“噪声”的幅度。波动频率约为每分钟0.5至2次。静脉注射12毫克/千克和16毫克/千克吗啡后出现的瞳孔缩小及随后的波动被纳洛酮（0.5毫克/千克静脉注射）阻断，但128毫克/千克吗啡可克服这种阻断。吗啡和纳洛酮处理后的吗啡的累积剂量 - 反应曲线得出pA2 = 6.8，这与使用其他效应和物种获得的值一致。在高强度光照下暴露后注射吗啡产生的瞳孔缩小比在正常光照下观察到的要少。
