Intraduodenal nutrient infusions cause an inhibition of antral motility and an increase in pyloric motility. The involvement of gastric myoelectrical activity in this intestinogastric feedback was studied. Electrogastrography and antropyloroduodenal manometry were performed in 10 healthy volunteers. The effects of 20-min infusions of 25% glucose (4 kcal/min) and saline were compared. Intraduodenal glucose infusions caused a decrease in the power of the dominant frequency in the electrogastrogram (P = 0.028), but the frequency itself remained unchanged. The total number of dysrhythmias increased (P = 0.035). An inhibition of antral motor activity (P = 0.001), an increase in the number of isolated pyloric pressure waves (P = 0.027), and an increase in basal pyloric tone (P = 0.001) were simultaneously recorded. The change in power during glucose infusion correlated positively with the change in the antral motility index (r_s = 0.50, P = 0.001). It is concluded that inhibition of gastric myoelectrical activity is one of the mechanisms underlying an inhibition of motor activity in the gastric antrum.