Effect of chronic food restriction on energy balance, thermogenic capacity, and brown-adipose-tissue activity in the rat.
Young male rats were fed a pelleted stock diet either ad libitum (control) or in restricted amounts (65% of control intake) for 17 d. Body energy gain and energy expenditure, determined from energy balance measurements, were reduced by 73 and 27% respectively compared to controls. Resting oxygen consumption was similar for both groups during the light phase but was significantly depressed in energy-restricted rats at night, and the thermogenic response to noradrenaline was also reduced in these animals. Brown-adipose-tissue mass, protein content, and mitochondrial protein were all decreased in the food-deprived rats, and specific and total depot mitochondrial GDP-binding capacity were 29 and 53% lower than controls. The reduced energy expenditure which occurs during food restriction may be due partly to a lower activity of brown adipose tissue which is associated with a decrease in thermogenic capacity.
D002001:Adipose Tissue, Brown / Q000502:physiology*; D000818:Animals; D001833:Body Temperature Regulation; D004038:Diet, Reducing; D002149:Energy Intake; D004734:Energy Metabolism; D006153:Guanosine Diphosphate / Q000378:metabolism; D007700:Kinetics; D008297:Male; D009638:Norepinephrine / Q000494:pharmacology; D009747:Nutritional Physiological Phenomena; D009929:Organ Size; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D014284:Triiodothyronine / Q000097:blood
D014284:Triiodothyronine; D006153:Guanosine Diphosphate; D009638:Norepinephrine