A behavioral analysis of the ingestion of glucose, maltose and maltooligosaccharide by rats

Glucose, maltose, and Polycose are stimuli that differ in their effectivene ss in stimulating ingestion in the rat. To understand better how variation in glucose chain length affects the ingestion of these compounds, we compar ed the effect of si?; concentrations of glucose, maltose, and maltooligosac charide (MOS) on the microstructure of the licking behavior of the rat. At the three lowest concentrations the order of effectiveness in stimulating i ngestion was MOS > maltose > glucose. At the three highest concentrations, there were no differences among the three compounds in volume ingested. As measured by initial rate of licking, the orosensory stimulating effectivene ss of the three compounds were ordered as MOS > maltose > glucose. The magn itude of the negative feedback signals were very similar for MOS and maltos e and greater than glucose at all but the highest two concentrations of glu cose, suggesting that glucose chain length, not caloric density, is respons ible for the differences in the magnitude of negative feedback. With the th ree lowest concentrations, the ordering of the compounds in their ability t o stimulate intake depended on orosensory stimulating ability. (C) 2000 Els evier Science Inc. All rights reserved.