To determine if preloads of glucose act preabsorptively or postabsorptively to inhibit intake, 18-day-old rat pups were deprived for 24 h and then provided with sweet milk during a 30-min independent ingestion test. Five minutes before the test, gastric preloads (5% body weight, BW) or intraperitoneal injections (4 ml/kg BW) of isotonic, hypotonic, and hypertonic solutions of glucose or 2-deoxy-D-glucose (2-DG) were administered. There were two major results: First, preloads of 20% glucose decreased intake much more than intraperitoneal injections of 20% glucose. Second, a preload of 20% 2-DG, which decreases, rather than increases glucose utilization, was as effective as a preload of 20% glucose in decreasing intake. These results are consistent with a preabsorptive osmotic mechanism, but not with a postabsorptive metabolic mechanism, for mediating most, if not all, of the inhibition of intake 5 min after preloads of 20% glucose in rats on postnatal day 18 (P18).
|Number of pages||5|
|Journal||Physiology and Behavior|
|State||Published - 2001|
Bibliographical noteFunding Information:
The authors thank Ofra Schwartz for technical assistance and Laurel Torres for processing the manuscript. Dr. Tsitolovska was supported by a fellowship from the Israel Ministry of Absorption. Dr. Smith was supported by MH40010.
- Gastric preloads
- Independent ingestion
- Ontogeny of food intake
- Osmotic load