title: Feeding behavior in rats subjected to gastrectomy or gastric bypass surgery.
abstract: OBJECTIVE
  Gastric bypass (GB) is usually designed to restrict food intake and to induce malabsorption. Gastric hormones have been thought to play a role in the regulation of food intake and body weight. The aim of the present study was to analyze feeding behavior after total gastrectomy (Gx) or GB in rats.
  
  
  METHODS
  Animals were subjected to Gx, GB, or sham operations. Eating and drinking behaviors after surgeries were assessed by a comprehensive laboratory animal monitoring system. Gastric hormones were measured by radioimmunoassay and energy density in feces by adiabatic bomb calorimeter.
  
  
  RESULTS
  Compared with sham operation, both Gx and GB reduced the body weight as measured during 3-8 weeks postoperatively, which was associated with increased energy expenditure per 100 g body weight. Daily accumulated food intake and meal size (during nighttime) were reduced following Gx, but not GB. The water intake (during daytime) was increased after Gx and GB. The energy density in feces was unchanged. Serum concentrations of ghrelin, obestatin, leptin, gastrin, and pancreastatin were greatly reduced after Gx.
  
  
  CONCLUSIONS
  Control of food intake and meal size was independent of the food reservoir function of the stomach. Surgical depletion of gastric hormones is associated with reduced meal size, but increased water intake.
authors.affiliation: Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway.
authors.forename: M W
authors.initials: MW
authors.lastname: Furnes
authors.forename: B
authors.initials: B
authors.lastname: Stenstrom
authors.forename: K
authors.initials: K
authors.lastname: Tømmerås
authors.forename: T
authors.initials: T
authors.lastname: Skoglund
authors.forename: S L
authors.initials: SL
authors.lastname: Dickson
authors.forename: B
authors.initials: B
authors.lastname: Kulseng
authors.forename: C-M
authors.initials: CM
authors.lastname: Zhao
authors.forename: D
authors.initials: D
authors.lastname: Chen
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005247:Feeding Behavior; D005743:Gastrectomy; D015390:Gastric Bypass; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley