Peripheral control of meal size in the rat: Effect of sham feeding on meal size and drinking rate.

3 sham-feeding studies using liquid diets and 9 mildly food-deprived male albino Sprague-Dawley rats suggest the existence of 2 types of control signals that determine liquid meal size. One appears to be a signal arising from activation of tension receptors in the stomach wall that set an upper limit on the size of a meal. The other appears to be a signal that controls the rate at which fluid is ingested. This 2nd type of signal may be a form of conditioned control of ingestion because repeated experience with sham feeding leads to progressive increases in the drinking rate. The progressive increase may reflect the extinction of a control signal that normally modulates the rate of fluid ingestion. (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)