title: Leptin-induced decrease in food intake is not associated with changes in gastric emptying in lean mice.
abstract: Chronic treatment with leptin regulates body weight and energy balance and reduces food intake in obese and lean mice. In 18- to 20-h fasted lean mice (C57BL/6, +/+), we examined the acute effect of a single intraperitoneal injection of recombinant mouse leptin (0.12 mg/kg) on food intake and gastric emptying. Leptin reduced food intake, with a peak inhibition at the 5th h postinjection (69 +/- 12%/h), although there was no change in food consumption at the 1st h. Leptin did not alter the 4-h rate of gastric emptying of a solid nutrient meal (free access to Purina chow for either 1-, 2-, or 4-h period). In normal Sprague-Dawley rats fasted for 18-20 h, a single intraperitoneal injection of recombinant mouse leptin (0.2 or 1.2 mg/kg) did not modify the 7-h cumulative or hourly food intake. These results show that a single intraperitoneal injection of recombinant mouse leptin reduces food intake within 5 h while not influencing gastric emptying of ingested food in lean mice. Sprague-Dawley rats are unresponsive to the food intake-reducing effect of a single intraperitoneal injection of mouse leptin at a dose 10-fold higher than that shown to be effective in mice within the first 4-7 h postinjection.
authors.affiliation: Center for Ulcer Research and Education, West Los Angeles Veteran's Affairs Medical Center, California 90073, USA.
authors.forename: M D
authors.initials: MD
authors.lastname: Barrachina
authors.forename: V
authors.initials: V
authors.lastname: Martínez
authors.forename: J Y
authors.initials: JY
authors.lastname: Wei
authors.forename: Y
authors.initials: Y
authors.lastname: Taché
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001066:Appetite / Q000187:drug effects*; D005247:Feeding Behavior / Q000187:drug effects*; D005746:Gastric Emptying; D020738:Leptin; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008820:Mice, Obese; D009765:Obesity; D011506:Proteins / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins / Q000494:pharmacology; D012016:Reference Values; D013851:Thinness; D013997:Time Factors
chemical_list: D020738:Leptin; D011506:Proteins; D011994:Recombinant Proteins