AJP - Gastrointestinal and Liver Physiology, Vol 244, Issue 1 95-100, Copyright © 1983 by American Physiological Society
Neural control of canine small intestinal interdigestive myoelectric complexes
J. Heppell, K. A. Kelly and M. G. Sarr
Our aim was to determine the role of the extrinsic and intrinsic nerves in
the regulation of the small intestinal interdigestive myoelectric complex
(IMC). In five dogs, the extrinsic nerves of the jejunoileum were divided,
but the bowel was left in situ with its wall intact. After recovery, IMCs
were detected in the duodenum (mean IMC period +/- SE = 188 +/- 19 min),
from where most migrated distally into and through the jejunum (84%). In
addition, extra IMCs appeared in the jejunum. Thus, the mean period of the
IMCs in the jejunum (134 +/- 10 min) was shorter than in the duodenum (P
less than 0.05). In contrast, after enteric transection and reanastomosis
at the ligament of Treitz and at a site 75 cm distal to the ligament, fewer
duodenal IMCs migrated into the jejunum (only 61%). However, extra IMCs
still arose in the jejunum, so that the mean period of IMCs in the jejunum
(111 +/- 5 min) was now similar to that in the duodenum (128 +/- 4 min, P
greater than 0.05). Our data were consistent with the hypothesis that
extrinsic nerves regulate the frequency of the small intestinal IMCs, while
an intact enteric wall aids in their distal propagation.
