Background: The colon exhibits electrical activity in the form of pacesetter potentials (PPs) and action potentials (APs); no activity is recorded in total colonic inertia (TCI). Electrical activity mediates
colonic motility. We have elsewhere demonstrated that 4 pacemakers initiate colonic electric activity. We investigated the hypothesis that the absence of electric activity in TCI is due to nonfunctioning
pacemakers and that their stimulation produces colonic motility and defecation.
Material/Methods: 19 patients with TCI were divided into 2 groups: a study group of 11 patients (age 42.6±6.8 years; 7 women) and a control group of 8 patients (age 41.4±6.3 years, 5 women). 7 healthy
volunteers (age 40.9±6.1 years, 5 women) were also studied. Pacing electrodes were endoscopically hooked to colonic mucosa: one stimulating and 2 or 3 recording. Stimulating electrodes
were applied to the 4 potential pacemaker sites located at the cecal pole, the cecocolonic junction, the mid-transverse colon, and the colosigmoid junction. Electrical activity was recorded before and during electrical stimulation.
Results: Colonic pacing of healthy volunteers caused a significant increase in the frequency, amplitude and conduction velocity of basal electric waves. Colonic pacing in the study group produced
PPs and APs, which varied between colonic segments. No waves were recorded from the control group in which the pacemakers were not activated.
Conclusions: Colonic pacing produces electrical activity in patients with TCI. This method can be applied for the treatment of constipation in these patients.

Keywords: Constipation - etiology, Constipation - physiopathology