Cabanac M, Swiergiel A H
Departement de Physiologie, Faculté de Medecine, Université Laval, Quebec City, Quebec, Canada.
Am J Physiol. 1989 Oct;257(4 Pt 2):R952-7. doi: 10.1152/ajpregu.1989.257.4.R952.
Rats were trained to forage 2 h daily in a zigzag alley at -15 degrees C. On experimental days food was placed in large amounts at a 1-, 4-, or 16-m distance from a warm shelter. The mass of food ingested and hoarded in the shelter by the rats was then recorded. The rats' body weights were depressed progressively by spacing the sessions with access to food, and then the animals were allowed to recover their initial body weight. The results showed that 2-h food intake was constant and did not vary as a function of body weight loss or the distance to reach the food (cost). On the other hand, the mass of food hoarded was a linear increasing function of body weight loss below the hypothetical set point for body weight and a decreasing linear function of the distance to the food. The linear regression of the mass of food hoarded on body weight with a negative slope (b) adequately depicted the rat's hoarding behavior: mass hoarded = a + b (body wt). The slope of this function decreased with increasing cost of food procurement. It is concluded that 1) the main response of the rat to starvation is food hoarding rather than ingestion and 2) the estimation of the body weight set point from hoarding is not affected by the costs of food procurement.
将大鼠训练为每天在 -15 摄氏度的曲折通道中觅食 2 小时。在实验日，将大量食物放置在距离温暖庇护所 1 米、4 米或 16 米处。然后记录大鼠在庇护所摄入和储存的食物量。通过安排获取食物的时间段，大鼠的体重逐渐下降，然后让动物恢复到初始体重。结果表明，2 小时的食物摄入量是恒定的，并不随体重减轻或到达食物的距离（成本）而变化。另一方面，储存的食物量是低于假设体重设定点的体重减轻的线性增加函数，并且是到食物距离的线性减少函数。储存食物量与体重的线性回归，其斜率为负（b），充分描述了大鼠的储存行为：储存量 = a + b（体重）。该函数的斜率随着食物获取成本的增加而降低。得出的结论是：1）大鼠对饥饿的主要反应是储存食物而非摄取食物；2）从储存情况估计体重设定点不受食物获取成本的影响。
