Schnur P, Bravo F, Trujillo M
Pharmacol Biochem Behav. 1983 Sep;19(3):435-9. doi: 10.1016/0091-3057(83)90116-8.
Two experiments investigated the dose and time related effects of morphine sulfate on wheel running behavior in golden Syrian hamsters. In Experiment 1, within-subject comparisons were made of the acute effects of 5, 20, and 40 mg/kg doses of morphine sulfate on running wheel activity. Compared with saline, morphine produced a dose related decrease in activity followed by a dose related recovery. At the lowest dose, the time effect curve was biphasic, with sustained hyperactivity following the recovery. In Experiment 2, the effects of low doses of morphine sulfate (0.5, 1.0, 2.5, 5.0 mg/kg) on running wheel activity were monitored for three days. Biphasic time effect patterns were evident at each dose: An initial period of hypoactivity was followed by recovery and subsequent hyperactivity. Moreover, repeated administration produced both tolerance and sensitization to morphine's effects on activity. Implications for mechanisms underlying the biphasic response pattern are discussed.
两项实验研究了硫酸吗啡对金黄地鼠转轮行为的剂量和时间相关效应。在实验1中，对5、20和40毫克/千克剂量的硫酸吗啡对转轮活动的急性效应进行了受试者内比较。与生理盐水相比，吗啡导致活动量出现剂量相关的减少，随后是剂量相关的恢复。在最低剂量时，时间效应曲线呈双相，恢复后出现持续的多动。在实验2中，对低剂量硫酸吗啡（0.5、1.0、2.5、5.0毫克/千克）对转轮活动的效应进行了三天监测。在每个剂量下双相时间效应模式都很明显：最初是活动减少期，随后是恢复和随后的多动。此外，重复给药会使机体对吗啡对活动的效应产生耐受性和敏化作用。文中讨论了双相反应模式潜在机制的相关意义。
