Figure 1.

Setup of high-resolution (HR) electrical mapping of canine stomach. A. Two electrode arrays each containing 128 electrodes arranged in a 16 by 8 configuration was placed on the anterior and posterior serosal surfaces of the stomach, in a mirrored fashion. B. Slow wave recordings were mostly obtained from lower gastric antrum region of the stomach, and reconstructed into activation map of anterior and posterior maps, representing one cycle of slow wave propagation. The red color represents early activation and the blue color represents later activation of slow waves. Each band of color represents an interval of 1 s, i.e., the larger the gap between two consecutive lines (isochrones), the more distance the slow wave propagated over the 1 s interval, therefore the faster the velocity in this region. C. A selection of recordings at 16 electrodes demonstrate the sequential propagation of slow waves (“a” denotes anterior electrodes, and “p” denotes posterior electrodes), with the dashed arrow representing the direction and wave plotted in the activation map in B. D. Classifications of gastric dysrhythmias and summary of subject numbers associated with each dysrhythmias following infusion of vasopressin.