Woods S C, Vasselli J R, Kaestner E, Szakmary G A, Milburn P, Vitiello M V
J Comp Physiol Psychol. 1977 Feb;91(1):128-33. doi: 10.1037/h0077307.
Previous researchers have reported that rats placed upon a feeding regimen such that they receive only 2 hr of food per day (meal-fed rats) develop hyperinsulinemia at the time of the day associated with feeding, even in the absence of food. Controls fed ad lib had no such response. In a series of several experiments, meal-fed rats had elevated insulin levels at only the specific time of the day associated with feeding, and the increment of insulin at that time could be eliminated with atropine. Free-feeding controls, on the other hand, always had higher insulin levels than the meal-fed rats, did not have an elevation of insulin at the time of the day that the meal-fed rats normally ate, and had insulin values that were unaffected by atropine. Further experimentation showed that hyperinsulinemia could become associated with arbitrary stimuli always associated with eating for meal-fed rats. It is concluded that the hyperinsulinemia of meal-fed rats associated with their feeding time is a learned response.
先前的研究人员报告称，给大鼠设定一种喂食方案，使其每天仅能获得2小时的食物（定时喂食大鼠），即使在没有食物的情况下，它们在与喂食相关的时间段也会出现高胰岛素血症。自由进食的对照组则没有这种反应。在一系列实验中，定时喂食大鼠仅在与喂食相关的特定时间段胰岛素水平升高，且此时的胰岛素增量可用阿托品消除。另一方面，自由进食的对照组胰岛素水平始终高于定时喂食大鼠，在定时喂食大鼠正常进食的时间段胰岛素水平不会升高，且胰岛素值不受阿托品影响。进一步的实验表明，高胰岛素血症可能与定时喂食大鼠进食时总是伴随的任意刺激有关。得出的结论是，定时喂食大鼠与喂食时间相关的高胰岛素血症是一种习得性反应。
