Colonic Electrical Stimulation Regulates Colonic Transit Via the Nitrergic Pathway in Rats

Abstract

Gastrointestinal electrical stimulation has been proposed for the treatment of gastrointestinal motor disorders. However, little is known about potential roles of colonic electrical stimulation (CES). The aim of this study was to evaluate the effect and mechanism of CES on colonic transit in conscious rats. Male rats (N = 14) were equipped with a pair of colonic serosal electrodes for stimulation and a catheter in the colon. Colonic transit was assessed in four randomized sessions with or without CES and with or without nitric oxide synthesis blocker, L-NNA, by calculating the output of phenol red from the anus every 10 min for 90 min. Results were as follows. (1) CES with trains of short pulses significantly enhanced colonic transit. Colonic emptying was 57.3 +/- 6.1% in the control session and 81.9 +/- 4.6% with CES at 90 min, reflecting a 43% increase. (2) L-NNA delayed colonic transit compared with saline and prevented the accelerative effect of CES on colonic transit. We conclude that CES has an excitatory effect on colonic transit and this excitatory effect may be mediated via the nitrergic pathway.

Effects and Mechanisms of Electrical Stimulation of the Stomach, Duodenum, Ileum, and Colon on Gastric Tone in Dogs

“…One of the previous studies reported a significant correlation between electrical stimulation-induced reduced gastric tone and reduced food intake in dogs. According to this, electrical stimulation of the gut that exerts an inhibitory effect on gastric tone (29) has potential for treating obesity [28,29,[31][32][33][34][35]. The findings of the current study suggest that stimulation location along the gut is not critical, so electrical stimulation may be performed based on the ease of implementation, such as convenience of surgery.…”

“…Although most clinicians and researchers have focused on gastric electrical stimulation in recent years, stimulating other parts of the gut has also been explored . Long-pulse GES is composed of single repeated pulses at a certain frequency (10 cpm in the present study) with the pulse width in the order of milliseconds (300 ms in this study), and has been shown to induce gastric and rectal relaxation [17,20,25,28]. The current study was designed to investigate the effects of electrical stimulation of various parts of the gut on gastric tone and to determine: (1) if the effect of electrical stimulation on gastric tone is organ-specific, distancerelated, or both; (2) the most potent method of stimulation for gastric tone; (3) if the effect of ileal electrical stimulation on gastric tone is mediated through the nitrergic pathway.…”

Pacing the gut in motility disorders

“…In a canine study with sequential (multichannel) colonic electrical stimulation, propagated colonic contractions were generated, and the movement of colonic content was accelerated [68,69]. Similar acceleration of colonic transit also was noted in rats [70].…”

Autonomic Consequences of Spinal Cord Injury

“…After a nontoxic, nonabsorbable marker or dye is fed to the stomach, the movement of the substance can be detected by X-ray or spectrophotometry throughout transportation in the GI tract during the period of any time interval (114,117,285). Visualization techniques including video fluoroscopy and magnetic resonance imaging (MRI) have been used in clinical or experimental settings to visualize GI motility by detection of solid food labeled with tracer (62,202,295). These noninvasive methods are attractive as they can be combined with sensory or motor functional measurements.…”