Stromberg Michael F, Mackler Scott A
Department of Psychiatry, University of Pennsylvania, Philadelphia, PA 19104, United States.
Pharmacol Biochem Behav. 2005 Oct;82(2):314-9. doi: 10.1016/j.pbb.2005.08.021. Epub 2005 Sep 30.
Outbred rats show significant variability in their propensity to consume alcohol. These experiments were designed to examine the effect of cocaine on the expression of motor activation or place preference in outbred Wistar rats that consumed either high or low quantities of alcohol. These rats were exposed to a 2-bottle limited access procedure and dichotomized into 2 groups, high (mean 0.91 g/kg/h) and low alcohol consumption (0.36 g/kg/h), and then exposed to repeated daily cocaine, 10 or 20 mg/kg, or saline injections. The low alcohol-consuming rats showed a significant increase in motor behavior to a cocaine challenge across both doses of cocaine, which did not differ from each other. The high alcohol-consuming rats showed a significant increase in motor behavior only at the high dose of cocaine. In Experiment 2 both high and low alcohol-consuming rats were exposed to a conditioned place preference procedure using cocaine 10 mg/kg. High alcohol-consuming rats showed a significant place preference to the cocaine-paired side while low consuming rats did not. The differential effects of cocaine on motor activating behavior and reward obtained in these experiments suggest that those factors determining whether an outbred Wistar rat will consume high or low amounts of alcohol are related, in part, to differential sensitivity of those neural systems underlying the effects of those drugs.
远交系大鼠在酒精消费倾向方面表现出显著的变异性。这些实验旨在研究可卡因对高酒精消费量或低酒精消费量的远交系Wistar大鼠运动激活或位置偏好表达的影响。这些大鼠接受两瓶限量摄入程序，并分为两组，即高酒精消费量组（平均0.91克/千克/小时）和低酒精消费量组（0.36克/千克/小时），然后每天重复注射可卡因（10或20毫克/千克）或生理盐水。低酒精消费量的大鼠在两种剂量的可卡因刺激下运动行为均显著增加，且两种剂量之间无差异。高酒精消费量的大鼠仅在高剂量可卡因刺激下运动行为显著增加。在实验2中，高酒精消费量和低酒精消费量的大鼠均接受使用10毫克/千克可卡因的条件性位置偏好程序。高酒精消费量的大鼠对与可卡因配对的一侧表现出显著的位置偏好，而低酒精消费量的大鼠则没有。这些实验中可卡因对运动激活行为和奖赏的不同影响表明，决定远交系Wistar大鼠酒精消费量高低的那些因素，部分与这些药物作用所涉及的神经系统的不同敏感性有关。
