The suppression of sucrose intake by cholecystokinin is scaled according to the magnitude of the orosensory control over feeding.

The intestinal hormone cholecystokinin (CCK) has been shown to play a role in the termination of food intake, however its behavioral mechanism of action remains to be determined. Recent work from this laboratory suggested that the suppression of intake with CCK is dependent upon the specific orosensory characteristics of the substance being consumed and that the hormone may suppress intake by altering the behavior maintaining characteristics of orosensory stimuli. The present study further investigated this suggestion by determining whether changes in the orosensory characteristics of food after the magnitude of the suppressive effect of CCK. Specifically, the magnitude of the CCK effect on the intake of sucrose solutions of various concentrations was determined on non-deprived rats. The results of this work indicate that the suppressive effect of synthetic CCK (CCK-8) cannot be overridden by increases in sucrose concentration. In contrast, it was found that over a range of sucrose concentrations, the magnitude of the CCK effect increased with solution concentration. Because sucrose concentration predicts both caloric density and the magnitude of orosensory control (as measured by grams consumed), it appears that CCK may act on this control to regulate meal size in proportion to the caloric density of the food.