Microprocessor controlled movement of solid colonic content using sequential neural electrical stimulation

Abstract

Background and aims: Invoked peristaltic contractions and movement of solid content have not been attempted in normal canine colon. The purpose of this study was to determine if movement of solid content through the colon could be produced by microprocessor controlled sequential stimulation. Methods: The study was performed on six anaesthetised dogs. At laparotomy, a 15 cm segment of descending colon was selected, the proximal end closed with a purse string suture, and the distal end opened into a collecting container. Four sets of subserosal stimulating electrodes were implanted at 3 cm intervals. The segment of bowel was filled with a mixture of dog food and 50 plastic pellets before each of 2-5 random sessions of non-stimulated or stimulated emptying. Propagated contractions were generated using microprocessor controlled bipolar trains of 50 Hz rectangular voltage having 20 V (peak to peak) amplitude, 18 second stimulus duration, and a nine second phase lag between stimulation trains in sequential electrode sets. Results: Electrical stimulation using the above mentioned parameters resulted in powerful phasic contractions that closed the lumen. By phase locking the stimulation voltage between adjacent sets of electrodes, propagated contractions could be produced in an aboral or orad direction. The number of evacuated pellets during the stimulation sessions was significantly higher than during the non-stimulated sessions (p<0.01). Conclusions: Microprocessor controlled electrical stimulation accelerated movement of colonic content suggesting the possibility of future implantable colonic stimulators.

Regional Difference in Colonic Motility Response to Electrical Field Stimulation in Guinea Pig

“…In contrast, when EFS was applied sequentially from the proximal range to distal range, aborad contractions were observed in the dog distal colon 22. However, our current study of guinea pig distal colon showed that a single EFS (oral or anal) initiated PCs which may propel intraluminal contents.…”

“…Previous studies showed that colonic motor responses to EFS were always localized and were not able to propel intraluminal contents over a distance in rats21 and dogs 22. In contrast, when EFS was applied sequentially from the proximal range to distal range, aborad contractions were observed in the dog distal colon 22.…”

“…However, there are few demonstrations that EFS evokes peristalsis. Previous studies showed that EFS failed to initiate peristalsis in the rat21 and dog colon 22. In contrast, when EFS was applied sequentially from the proximal to distal colon, aborad contractions were observed in the dog distal colon 22.…”

“…Previous studies showed that EFS failed to initiate peristalsis in the rat21 and dog colon 22. In contrast, when EFS was applied sequentially from the proximal to distal colon, aborad contractions were observed in the dog distal colon 22. Even in normal conditions, shortly propagated bursts in the oral directions, anti-peristalsis, are observed in the rat11 and dog colon8 in vivo.…”

Stopping mechanism for capsule endoscope using electrical stimulus

“…Moreover, appropriate electrical stimulus parameters were determined on the basis of the MSFF. The electrical stimulus method was originally used to provide locomotion ability or medical treatment [2,9,11,16,19,20,21,26]. The original ESC caused a contraction at the edges of the capsule, and the capsule was propelled along the lumen.…”