Ahmed S H, Koob G F
Division of Psychopharmacology, Department of Neuropharmacology, CVN-7, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA.
Science. 1998 Oct 9;282(5387):298-300. doi: 10.1126/science.282.5387.298.
Differential access to cocaine self-administration produced two patterns of drug intake in rats. With 1 hour of access per session, drug intake remained low and stable. In contrast, with 6 hours of access, drug intake gradually escalated over days. After escalation, drug consumption was characterized by an increased early drug loading and an upward shift in the cocaine dose-response function, suggesting an increase in hedonic set point. After 1 month of abstinence, escalation of cocaine intake was reinstated to a higher level than before. These findings may provide an animal model for studying the development of excessive drug intake and the basis of addiction.
大鼠对可卡因自我给药的不同获取方式产生了两种药物摄入模式。每次给药1小时，药物摄入量保持较低且稳定。相比之下，每次给药6小时，药物摄入量在数天内逐渐增加。摄入量增加后，药物消耗的特点是早期药物负荷增加以及可卡因剂量反应函数向上移动，这表明享乐设定点增加。禁欲1个月后，可卡因摄入量的增加恢复到比以前更高的水平。这些发现可能为研究过度药物摄入的发展及成瘾基础提供一个动物模型。
