[Studies of pacing the canine stomach with electric stimulation for its possible clinical application (author's...

In dogs anesthetized by pentobarbital sodium, bipolar stimulating and recording electrodes were implanted on the gastric serosal surface and pacing effect of stimuli of rectangular current on the basic electric rhythm (BER) was examined. For judgement of pacing, the appearance of a compensatory pause after off-stimulation was a useful criterion. When BER was recorded at the oral side of stimulation, antiperistaltic one was added. Maximum driven frequency (MDF) was 6.0 +/- 0.6 (SD) cycles/min. The relation between stimulus interval (x) and BER interval (y) was represented by y = x in the stimuli below MDF. In the stimulus frequency until 2 times of MDF above MDF, it was replaced by y = 2x. Phase lag between BERs of two separated points was increased as the stimulus frequency was increased up to MDF. This tendency was observed similarly within 2 times of MDF above MDF. Using a gastrointestinal fiberscope, electric stimulation was delivered from the gastric mucosal side, while BER was recorded from the serosal side in 5 dogs and was recorded with electrodes through the endoscope in 2 dogs. Pacing was possible, too. These results may indicate that pacing and recording of the BER using gastrointestinal fiberscope are applicable clinically.