Alterations of energy and substrate metabolism in rats with large
and sustained changes in daily food intake.
Wang, Jianfang F., and Henry S. Koopmans.
Dept. of Medical Physiology, University of Calgary, Calgary,
Alberta, Canada T2N 4N1
APStracts 2:0257R, 1995.
Energy expenditure was measured in one-way crossed-intestines rats
using indirect calorimetry to examine the role of energy metabolism
in body weight control. The intestinal surgery was done according to
Koopmans (Brain Res. Bull. 14:595-603, 1985). The food-losing rats
increased daily food intake from 70.8 to 126.3 g/day while their
partners decreased intake from 67.1 to 38.7 g/day (P<.001).
Compared with levels before surgery, the food-losing rats showed
slightly increased oxygen consumption (VO2) (1.31 vs 1.28 L/Hr/kg)
and metabolic rate (6.62 vs 6.39 kcal/Hr/kg) and largely increased
carbon dioxide production (VO2) (1.31 vs 1.22 L/Hr/kg, P<.01),
while their food-gaining partners had significantly decreased both
VO2 (1.12 vs 1.25 L/Hr/kg, P<.01) and metabolic rate (5.76 vs
6.26 kcal/Hr/kg). The food-gaining rats had higher respiratory
quotient values than their partners (1.076 vs 0.999, P<.01)
indicating more fatty acid synthesis. These results suggest that
daily food intake and energy expenditure increase and decrease
together, despite the fact that about the same amount of food has
been absorbed from their intestines.
Received 3 February 1995; accepted in final form 5 July 1995.
APS Manuscript Number R90-5.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 23 September 1995.