Leptin-induced decrease in food intake is not associated with
changes in gastric emptying in lean mice.
Barrachina, Maria Dolores, Vicente Martinez, Jen Yu Wei, and Yvette
Tach[acute]e.
Digestive Diseases Research Center, West Los Angeles VA Medical
Center, Department of Medicine and Brain Research Institute,
University of California, Los Angeles, California, 90073
APStracts 3:0440R, 1996.
Leptin-induced decrease in food intake is not associated with changes
in gastric emptying in lean mice. Am. J. Physiol. (Regulatory
Integrative Comp. Physiol.)- Chronic treatment with leptin regulates
body weight and energy balance and reduces food intake in obese and
lean mice. In 18-20 h fasted lean mice (C57BL/6, +/+), we examined
the acute effect of a single intraperitoneal (i.p.) 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 post-injection (69 +/- 12%/h) while 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 i.p. 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 i.p. 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 i.p. injection of mouse leptin at a dose 10 fold higher than
that shown to be effective in mice within the first 4-7 h post
-injection.
Received 23 August 1996; accepted in final form 3 december 1996.
APS Manuscript Number R511-6.
Article publication pending Am. J. Physiol. (Regulatory Integrative
Comp. Physiology).
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 31 December 1996