Independence of canine gastric and duodenal pacesetter potentials shown by electric pacing.

Our objective was to determine if the canine gastric pacesetter potential spreads across the pylorus to influence the duodenal pacesetter potential, and vice versa. Electric pacing of the gastric corpus increased the frequency of the gastric pacesetter potential and slowed the velocity of its aborad propagation, but gastric pacing did not change the frequency of the duodenal pacesetter potential or alter the velocity or aborad direction of its propagation. Electric pacing of the distal duodenum increased the frequency of the proximal duodenal pacesetter potential, reversed its direction of propagation from aborad to orad, and slowed its velocity of propagation. However, duodenal pacing did not alter the frequency, velocity, or direction of propagation of the gastric pacesetter potential. Our conclusion is that the gastric pacesetter potential and the duodenal pacesetter potential are each independent of the frequency, velocity, and direction of propagation of the other.