Continuous flow microcalorimetric measurement of heat production in white adipose tissue from obese (ob/ob) mice and their lean littermates.
Heat production, free fatty acid and glycerol release from white adipose tissue fat pads from obese (ob/ob) mice and their lean littermates are determined. Heat production was significantly lower in obese mice compared to lean mice when expressed on wet weight basis but not when expressed on DNA basis. Noradrenaline significantly increased the heat production in fat pads from both groups of animals. However, the increase in heat production due to noradrenaline addition in fat pads from lean mice was significantly higher than in fat pads from obese mice. The release of free fatty acids and glycerol before incubation with noradrenaline was similar from fat pads from both groups of animals. Addition of noradrenaline to the fat pads increased the release of free fatty acids and glycerol in both groups of animals, but the increase was significantly larger from fat pads from lean mice. In the absence of noradrenaline the free fatty acid/glycerol ratio (mol/mol) in the effluent was 7.9:1 and 4.8:1 for lean mice and obese mice, respectively. In the presence of noradrenaline the ratio decreased to 3:1 for both groups of animals.
D000273:Adipose Tissue / Q000187:drug effects / Q000502:physiology*; D000818:Animals; D001833:Body Temperature Regulation / Q000187:drug effects; D002151:Calorimetry; D004247:DNA / Q000378:metabolism; D004734:Energy Metabolism; D005230:Fatty Acids, Nonesterified / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D066298:In Vitro Techniques; D051379:Mice; D008820:Mice, Obese; D009638:Norepinephrine / Q000494:pharmacology; D009765:Obesity / Q000503:physiopathology*
D005230:Fatty Acids, Nonesterified; D004247:DNA; D005990:Glycerol; D009638:Norepinephrine