Chwalibog A, Jakobsen K, Tauson A H, Thorbek G
Royal Veterinary and Agricultural University, Department of Animal Science and Animal Health, Frederiksberg, Copenhagen, Denmark.
Comp Biochem Physiol A Mol Integr Physiol. 1998 Dec;121(4):423-9. doi: 10.1016/s1095-6433(98)10153-8.
A total of 36 Wistar rats were fed a commercial diet to a stipulated live weight of 75 g (Group A), 100 g (Group B) and 225 g (Group C). All rats were measured in energy balance experiments, in which the animals were fed near maintenance level, followed by a period of fasting with measurements of the gas exchange. The rats in Group A, B and C were fasted for 2, 3 and 4 days, respectively. The minimum heat production on the last day of fasting for all groups was proportional to metabolic body weight (kg0.75) with a regression: heat production, kJ day-1 = 321 x kg0.75 (R2 = 0.994). In rats fed near maintenance level, heat production was provided by oxidation of carbohydrates in 80-85%, oxidation of protein was 10-15%, while oxidation of fat contributed less than 10%. It is suggested that in the fasting period, the contribution to the total heat production from oxidized carbohydrate and fat depended on the size of the fat depots, a large fat depot giving rise to fat oxidation. On the last day of fasting, 24, 51 and 90% of the total heat originated from fat oxidation in Group A, B and C, respectively.
总共36只Wistar大鼠被喂食市售饲料，直至达到规定的活体重，分别为75克（A组）、100克（B组）和225克（C组）。所有大鼠都参与了能量平衡实验，在实验中，动物被喂食接近维持水平的食物，随后进行一段时间的禁食，并测量气体交换。A组、B组和C组的大鼠分别禁食2天、3天和4天。所有组在禁食最后一天的最低产热量与代谢体重（kg0.75）成正比，回归方程为：产热量，kJ·天-1 = 321×kg0.75（R2 = 0.994）。在喂食接近维持水平的大鼠中，80 - 85%的产热量由碳水化合物氧化提供，10 - 15%由蛋白质氧化提供，而脂肪氧化贡献不到10%。有人提出，在禁食期间，氧化的碳水化合物和脂肪对总产热量的贡献取决于脂肪储存量的大小，脂肪储存量大则会导致脂肪氧化。在禁食的最后一天，A组、B组和C组分别有24%、51%和90%的总热量来自脂肪氧化。
