Meal reduces sensitivity of the stomach to pharmacologically induced dysrhythmia

The aim of this study was to determine whether food ingestion causes a change in the susceptibility of the stomach to dysrhythmia or in the characteristics of gastric dysrhythmia. The susceptibility of the stomach to develop dysrhythmia was measured by determining the median effective dose of four different drugs known to produce gastric dysrhythmia. These drugs were epinephrine, PGE₂, met-enkephalin, and glucagon. The median effective dose for inducing gastric dysrhythmia was measured in four healthy conscious dogs by Dixon's up-and-down method during fasting and after feeding. The median effective dose of epinephrine, PGE₂, met-enkephalin, and glucagon were higher after feeding (16.6, 16.6, 35.1,>221 μg/kg, respectively) than during fasting (1.7, 5.2, 11.1, 61.0 μg/kg, respectively). The results indicate that feeding renders the stomach less susceptible to pharmacologically induced dysrhythmia. However, characteristics of gastric dysrhythmias, such as site of origin and direction of propagation, were similar whether they occurred during fasting or after feeding.