Fig. 1

Effects of intragastric infusion of IMP on the afferent discharge rate of a vagal gastric nerve (VGA) filament. a Example of intragastric infusion of 30 mM IMP on VGA activity. Actual wave recording at each point was displayed before (left) and after 30 min of (right) intragastric infusion of IMP (Top). Representative recording of gastric afferent discharge displayed as a sequential rate histogram after intragastric infusion of IMP (Bottom). Arrowheads indicate the points at which the IMP solution was infused. The vertical bar indicates 100 impulses/5 s. The horizontal bar indicates 30 min. b The time course of changes in VGA activity from 5 different rats in which 30 mM IMP was administrated. *p < 0.05, **p < 0.01, one-way repeated ANOVA with the post-hoc Dunnett’s method. Vertical bars indicate ±SEM. c Dose-dependent effects of luminal IMP on the afferent discharge rate of VGA activity. Each IMP solution (1, 3, 10, and 30 mM) was introduced into the rat stomach, and the mean change in discharge rate above baseline at 30 min was plotted. Columns and vertical bars represent mean ± SEM from 5 different rats