McNamara R K, Whishaw I Q
Department of Psychology, University of Lethbridge, Alberta, Canada.
Psychopharmacology (Berl). 1990;101(2):214-21. doi: 10.1007/BF02244129.
The "security hypothesis" suggests food hoarding by rats serves to preempt attack and therefore might be motivated by "anxiety". The "object value" hypothesis suggests rats hoard objects that they perceive as valuable as related to some state or need. These hypotheses were evaluated with the anxiolytic drug diazepam, which is purported to both decrease anxiety and increase motivation to eat, and which accordingly either may decrease or increase hoarding. Using a new hoarding paradigm, diazepam (Valium: 0.25-5 mg/kg), was found to produce a dose-related reduction in hoarding that was dependent upon food pellet size and that was reversed by flumazenil (Ro 15-1788), a benzodiazepine receptor antagonist. Diazepam also slowed eating speed, blocked "dodging", a movement used to initiate hoarding, and impaired spatial navigation in a learning-set swimming pool task. The results fail to support the object value hypothesis of hoarding. Since perception of food size, motivation, motor ability and spatial abilities all probably contribute to successful food hoarding, the results provide several explanations other than, or in addition to, anxiety reduction for the drug's effects on hoarding. Nevertheless, the study provides a number of new sensitive measures of the effects of anxiolytic drugs and new insights into their behavioral effects.
“安全假说”认为，大鼠囤积食物是为了先发制人地抵御攻击，因此可能是由“焦虑”驱动的。“目标价值”假说认为，大鼠会囤积它们认为与某种状态或需求相关的有价值的物品。这些假说通过抗焦虑药物地西泮进行了评估，据称地西泮既能减轻焦虑，又能增加进食动机，因此可能会减少或增加囤积行为。采用一种新的囤积范式，研究发现地西泮（安定：0.25 - 5毫克/千克）会使囤积行为出现与剂量相关的减少，这种减少取决于食物颗粒大小，并且会被苯二氮䓬受体拮抗剂氟马西尼（Ro 15 - 1788）逆转。地西泮还会减慢进食速度，阻止“躲避”（一种用于开始囤积行为的动作），并在学习集游泳池任务中损害空间导航能力。研究结果不支持囤积行为的目标价值假说。由于对食物大小的感知、动机、运动能力和空间能力都可能对成功的食物囤积有所贡献，因此这些结果为该药物对囤积行为的影响提供了除减轻焦虑之外或之外的多种解释。尽管如此，该研究提供了一些关于抗焦虑药物效果的新的敏感测量方法以及对其行为影响的新见解。
