Shelton K L, Macenski M J, Meisch R A
Substance Abuse Research Center, Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, 77030-3497, USA.
Pharmacol Biochem Behav. 1998 Dec;61(4):367-74. doi: 10.1016/s0091-3057(98)00100-2.
Studies report a high incidence of alcohol abuse in methadone maintenance patients. There is, however, little data on the reinforcing effects of combinations of ethanol and methadone. In the present study, oral self-administration of a combination of 1% (w/v) ethanol and 0.2 mg/ml methadone was compared to each drug alone in three rhesus monkeys in which methadone alone was not a reinforcer. In Experiment 1, ethanol and the combination, but not methadone alone, served as reinforcers. In Experiment 2, there was no preference for ethanol or the combination at fixed ratio (FR) 8 or 16. When the FR size was doubled (FR 16 or 32), all three animals preferred the combination to 1% ethanol. Experiment 3 further examined the effect of work requirement on preference for ethanol or the combination by varying FR values [1, 2, 4, 8, 16, or 32]. At lower FRs, ethanol was significantly preferred to the combination. As FR was increased, there was a significant reduction in preference for ethanol over the combination. The results show that an ethanol + methadone combination will be orally self-administered by monkeys and suggest that work requirement differentially modifies preference for the combination and ethanol alone.
研究报告称美沙酮维持治疗患者中酒精滥用的发生率很高。然而，关于乙醇与美沙酮联合使用的强化作用的数据却很少。在本研究中，将1%（w/v）乙醇与0.2mg/ml美沙酮的组合口服自我给药情况，与单独使用每种药物在三只恒河猴身上进行了比较，这三只恒河猴单独使用美沙酮时不会产生强化作用。在实验1中，乙醇及其组合可作为强化物，但单独的美沙酮则不能。在实验2中，在固定比率（FR）为8或16时，对乙醇或其组合没有偏好。当FR大小翻倍（FR为16或32）时，所有三只动物都更喜欢该组合而非1%的乙醇。实验3通过改变FR值[1、2、4、8、16或32]进一步研究了工作要求对乙醇或其组合偏好的影响。在较低的FR值时，乙醇明显比该组合更受青睐。随着FR的增加，相对于该组合，对乙醇的偏好显著降低。结果表明，猴子会口服自我给药乙醇+美沙酮的组合，这表明工作要求会不同程度地改变对该组合和单独乙醇的偏好。
