Gosselin C, Cabanac M
Département de physiologie, Faculté de Médecine, Université Laval, Québec, Canada.
Physiol Behav. 1996 Sep;60(3):817-21. doi: 10.1016/0031-9384(96)00093-5.
The mass of food hoarded by rats given access to food only 2 h per day is proportional to the rats' body weight deficit. The intersect of the regression line of hoarded food plotted against body weight gives an indication of the body weight set-point. In the present work, the hoarding behavior of six obese and six control rats was measured every day at various body weights from 8 to 24 weeks of age. Every other week the animals were anesthetized and their percentage of fat was measured in vivo with a total body electrical conductivity method (TOBEC). Lean mass and body length of the obese, and their controls, increased similarly in both groups over the period of the measurements. On the other hand, the body weights increased more in obese, from 174 +/- 5 to 729 +/- 18 g (n = 6), than in controls, from 157 +/- 5 g to 452 +/- 14 g (n = 6). The body weight set-point, calculated every other week for both groups of rats, increased progressively with age. At the age of 24 weeks, the mean set-point for body weight regulation was 758 +/- 13 g in obese and 467 +/- 12 g in controls. This result suggests that the obese fa/fa rat defends its fat content, or a variable correlated to the fat content.
每天仅能获取2小时食物的大鼠所囤积食物的量与大鼠的体重亏空成正比。以囤积食物量为纵坐标、体重为横坐标绘制的回归线的交点可指示体重设定点。在本研究中，对6只肥胖大鼠和6只对照大鼠从8周龄至24周龄不同体重时的囤积行为进行了每日测量。每隔一周对动物进行麻醉，并用全身电阻抗法（TOBEC）在体内测量它们的脂肪百分比。在测量期间，肥胖大鼠及其对照大鼠的瘦体重和体长在两组中均以相似的方式增加。另一方面，肥胖大鼠的体重增加更多，从174±5克增加到729±18克（n = 6），而对照大鼠从157±5克增加到452±14克（n = 6）。两组大鼠每隔一周计算一次的体重设定点随年龄逐渐增加。在24周龄时，肥胖大鼠体重调节的平均设定点为758±13克，对照大鼠为467±12克。这一结果表明肥胖的fa/fa大鼠会维持其脂肪含量或与脂肪含量相关的一个变量。
