Samson H H, Tolliver G A, Schwarz-Stevens K
Alcohol and Drug Abuse Institute, University of Washington, Seattle 98195.
Alcohol. 1991 Jan-Feb;8(1):43-53. doi: 10.1016/0741-8329(91)91248-z.
Two groups of rats (male, Long-Evans) were studied in a continuous access situation, in which ethanol, food and water intake patterns were monitored, 23 h/day. One group of rats was initiated to lever press for ethanol prior to study in the continuous access situation by use of a secondary-conditioning procedure. The other group had no prior initiation. It was found that the ethanol self-administration pattern of the initiated rats was similar to a previous study using another initiation procedure. After four weeks, the noninitiated group also demonstrated an ethanol intake pattern similar to initiated animals. However, the specific nature of individual ethanol drinking bouts in the noninitiated animals was found to be different, suggesting that initiation resulted in larger and more ethanol-drinking bouts. In addition, the noninitiated animals failed to show any home-cage shift in ethanol preference, which is observed after the use of the initiation procedures. The only major difference found between the sucrose-substitution initiation procedure and the secondary-conditioning procedure occurred when response requirements to obtain food were increased. In this situation, ethanol intake increased only in the sucrose-substitution initiated animals. The relation of this finding to the underlying theoretical basis for each type of initiation procedure is discussed.
在持续获取条件下对两组雄性Long-Evans大鼠进行了研究，每天23小时监测它们的乙醇、食物和水的摄入模式。一组大鼠在持续获取条件下进行研究之前，通过二级条件作用程序开始按压杠杆获取乙醇。另一组大鼠则没有预先开始训练。结果发现，预先训练的大鼠的乙醇自我给药模式与之前使用另一种起始程序的研究相似。四周后，未预先训练的组也表现出与预先训练的动物相似的乙醇摄入模式。然而，未预先训练的动物个体乙醇饮用发作的具体性质被发现有所不同，这表明预先训练导致了更大且更多的乙醇饮用发作。此外，未预先训练的动物在乙醇偏好上没有表现出任何笼内转移，而这在使用起始程序后是可以观察到的。蔗糖替代起始程序和二级条件作用程序之间发现的唯一主要差异发生在获取食物的反应要求增加时。在这种情况下，仅在蔗糖替代起始的动物中乙醇摄入量增加。讨论了这一发现与每种起始程序潜在理论基础的关系。
