Fat balance and hepatic mitochondrial function in response to fat feeding in mature rats.
OBJECTIVE
To study the effects of fat feeding on fat balance and hepatic mitochondrial function in postpubertal male rats.


METHODS
Rats were fed low fat, medium fat or high fat diet for 15 days.


METHODS
Energy balance, body composition, resting metabolic rate (RMR), mitochondrial state 3 and state 4 oxygen consumption rates, succinic dehydrogenase (EC 1.3.99.1) and mitochondrial alpha-glycerophosphate dehydrogenase (EC 1.1.1.8) activities.


RESULTS
Rats fed medium fat or high fat diet, in comparison with rats fed low fat diet, showed a significantly greater metabolisable energy intake and energy expenditure. In addition, body energy and lipid gains were significantly higher in rats fed medium fat or high fat diet than in rats fed low fat diet. Mitochondrial respiration and enzymatic activities were not affected by fat feeding.


CONCLUSIONS
These results indicate that in postpubertal rats fed high fat diets, the increase in energy expenditure counteracts only in part the excess fat deposition. This is probably due to the impairment in regulatory responses, and enhances thermogenesis.
Iossa
S
S
Department of General and Environmental Physiology, University of Naples FEDERICO II, Italy.
Lionetti
L
L
Mollica
M P
MP
Barletta
A
A
Liverini
G
G
D000273:Adipose Tissue; D000818:Animals; D001481:Basal Metabolism; D001823:Body Composition; D001835:Body Weight; D004041:Dietary Fats / Q000008:administration & dosage*; D002149:Energy Intake; D004734:Energy Metabolism; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D005993:Glycerolphosphate Dehydrogenase / Q000378:metabolism; D050356:Lipid Metabolism; D008297:Male; D008930:Mitochondria, Liver / Q000502:physiology*; D009243:NAD / Q000378:metabolism; D010101:Oxygen Consumption; D051381:Rats; D017208:Rats, Wistar; D013385:Succinate Dehydrogenase / Q000378:metabolism
D004041:Dietary Fats; D009243:NAD; D005182:Flavin-Adenine Dinucleotide; D005993:Glycerolphosphate Dehydrogenase; D013385:Succinate Dehydrogenase