Effect of isocaloric diets and sibutramine on food intake, body mass variation and serum TNF-alpha levels in rats.
OBJECTIVE
The effect of isocaloric diets and sibutramine on dietary behaviour and TNF-alpha is poorly understood. The aim of the study was to investigate the effects of isocaloric diets and sibutramine on food intake, body mass variation and serum TNF-alpha in free-feeding rats.


METHODS
Three groups of male Wistar rats (n = 63) were fed a high-fat diet, high-carbohydrate diet or high-protein diet for 13 weeks. In the last 3 weeks, each group was divided into 3 subgroups. Each subgroup received sibutramine 5 mg/kg, sibutramine 10 mg/kg or vehicle. Food intake was measured daily during the last week of the experiment; serum TNF-alpha was assayed and the body weight increasing rate was calculated.


RESULTS
The high-fat diet was associated with increased food intake, a greater weight gain ratio and increased TNF-alpha levels. Sibutramine treatment did not affect the dietary behaviour of high-protein- or high-carbohydrate-fed rats, while it significantly attenuated the daily food intake and body weight gain rate in the high-fat group, at the dose of 10 mg/kg. TNF-alpha levels were not affected by sibutramine.


CONCLUSIONS
High-fat feeding was associated with an increase in daily food intake, TNF-alpha levels and body weight gain rate, as well as with enhanced responsiveness to the anorectic effects of sibutramine. However, sibutramine did not affect TNF-alpha.
Trapali
M
M
Department of Pharmacology, Medical School, University of Athens, Athens, Greece.
Liapi
C
C
Perelas
A
A
Perrea
D
D
Stroubini
T
T
Dontas
I
I
Couvari
E
E
Mavri
M
M
Galanopoulou
P
P
D000818:Animals; D001067:Appetite Depressants / Q000008:administration & dosage / Q000494:pharmacology*; D001835:Body Weight / Q000187:drug effects*; D003503:Cyclobutanes / Q000008:administration & dosage / Q000494:pharmacology*; D004032:Diet; D004040:Dietary Carbohydrates / Q000008:administration & dosage / Q000378:metabolism; D004041:Dietary Fats / Q000008:administration & dosage / Q000378:metabolism; D004044:Dietary Proteins / Q000008:administration & dosage / Q000378:metabolism; D004435:Eating / Q000187:drug effects*; D002149:Energy Intake; D004797:Enzyme-Linked Immunosorbent Assay; D005247:Feeding Behavior; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000097:blood*; D015430:Weight Gain / Q000187:drug effects
D001067:Appetite Depressants; D003503:Cyclobutanes; D004040:Dietary Carbohydrates; D004041:Dietary Fats; D004044:Dietary Proteins; D014409:Tumor Necrosis Factor-alpha; C058254:sibutramine