Razafimanalina R., Mormède P., Velley L.
Laboratoire Génétique du Stress et Neurobiologie de l'Adaptation INSERM, CJF 9405 INRA, Université de Bordeaux II, B.P. 10, 146 rue Léo Saignat, 33076 Bordeaux Cedex, France.
Behav Pharmacol. 1996 Jan;7(1):78-84.
Rats of the Roman high-(RHA) and low-avoidance (RLA) lines are known to differ in alcohol preference, since the RHA rats freely consume more ethanol than RLA animals. In order to investigate whether this difference in alcohol intake could be due to an alteration of the gustatory quality of ethanol induced by the selection, we compared taste preference and aversion responses of RHA and RLA rats in four procedures: saccharin-water choice; gustatory negative contrast; quinine-water choice and 10% v/v alcohol-water choice. Our results confirm that RHA rats drink more alcohol than RLA rats. In the saccharin-water choice task, RHA rats tended to show higher preference than RLA rats for the most palatable concentrations, while their aversion to the highest concentration of saccharin (50mM) was smaller than the aversion shown by RLA rats. The negative gustatory contrast test did not clearly differentiate the two lines, although only RHA rats showed significant negative contrast. Lastly, while RLA rats showed only aversion to quinine as the concentration increased, RHA rats did not show any aversion and preferred quinine to water at mid-range concentrations. To explain these results three hypotheses are briefly discussed: first, selective breeding for high avoidance learning could have enhanced brain reinforcement processes implicated in the evaluation of palatability. Secondly, selective breeding could have decreased aversiveness to quinine-adulterated solutions, as well as to saccharin and alcohol solutions which include a quinine-like taste component. Lastly, the present results suggest that the RHA rats may be high sensation-seekers whereas RLA animals are low sensation-seekers.
已知罗马高回避（RHA）品系和低回避（RLA）品系的大鼠在酒精偏好上存在差异，因为RHA大鼠比RLA大鼠自由摄取的乙醇更多。为了研究这种酒精摄入量的差异是否可能是由于选择过程中乙醇味觉质量的改变所致，我们在四种实验程序中比较了RHA和RLA大鼠的味觉偏好和厌恶反应：糖精-水选择；味觉负对比；奎宁-水选择和10%（v/v）酒精-水选择。我们的结果证实，RHA大鼠比RLA大鼠饮用更多的酒精。在糖精-水选择任务中，RHA大鼠在最可口的浓度下比RLA大鼠表现出更高的偏好，而它们对最高浓度糖精（50mM）的厌恶程度小于RLA大鼠表现出的厌恶程度。味觉负对比测试没有明确区分这两个品系，尽管只有RHA大鼠表现出显著的负对比。最后，虽然随着浓度增加RLA大鼠仅表现出对奎宁的厌恶，但RHA大鼠没有表现出任何厌恶，并且在中等浓度下更喜欢奎宁而不是水。为了解释这些结果，简要讨论了三个假设：第一，针对高回避学习的选择性育种可能增强了与适口性评估相关的大脑强化过程。第二，选择性育种可能降低了对掺有奎宁的溶液以及含有类似奎宁味道成分的糖精和酒精溶液的厌恶感。最后，目前的结果表明RHA大鼠可能是高感觉寻求者，而RLA大鼠是低感觉寻求者。
