Kelly T H, Thompson T
Department of Psychology, University of Minnesota, Minneapolis 55455.
Arch Int Pharmacodyn Ther. 1988 May-Jun;293:20-36.
Five adult male White Carneaux pigeons, maintained at approximately 70, 80 or 90% free-feeding weight, were administered methadone (0.5, 1.5, and 2.5 mg/kg) prior to sessions of key pecking maintained under 5-min fixed-interval schedules of food presentation. Increasing deprivation levels attenuated the rate-decreasing effects of methadone. Methadone effects on pause time were unchanged. Three pigeons, maintained at 80% free-feeding weight were then administered methadone hydrochloride (0.62, 1.25 and 2.5 mg/kg) and naloxone hydrochloride (.0001, .0003, .001, .003 or .01 mg/kg) alone and in combination while responding under these same contingencies. Naloxone had no systematic behavioral effects alone but antagonized methadone's effects on fixed-interval responding and pausing. Naloxone also altered methadone's rate-dependent effects. These results suggest the behavioral effects of methadone are differentially altered following food-deprivation and opiate antagonist manipulations.
五只成年雄性白卡诺鸽，维持在自由采食体重的约70%、80%或90%，在按5分钟固定间隔食物呈现时间表维持的啄键实验前给予美沙酮（0.5、1.5和2.5毫克/千克）。剥夺水平的增加减弱了美沙酮的速率降低作用。美沙酮对停顿时间的影响未改变。然后，将三只维持在自由采食体重80%的鸽子在相同条件下做出反应时单独及联合给予盐酸美沙酮（0.62、1.25和2.5毫克/千克）和盐酸纳洛酮（0.0001、0.0003、0.001、0.003或0.01毫克/千克）。纳洛酮单独使用时没有系统性行为效应，但拮抗了美沙酮对固定间隔反应和停顿的影响。纳洛酮还改变了美沙酮的速率依赖性效应。这些结果表明，食物剥夺和阿片类拮抗剂处理后，美沙酮的行为效应会有不同改变。
