AJP - Gastrointestinal and Liver Physiology, Vol 254, Issue 4 595-G601, Copyright © 1988 by American Physiological Society
Giant migrating contractions of the canine cecum
S. K. Sarna, K. R. Prasad and I. M. Lang
Department of Surgery, Medical College of Wisconsin, Milwaukee 53226.
We investigated cecal motor activity and its coordination with ileal and
colonic motor activities in five conscious dogs instrumented with
strain-gauge transducers. Both ileum and colon exhibited the usual
migrating motor complexes (MMCs) that were independent of each other. Cecum
had no motor complexes, but it periodically generated giant migrating
contractions (GMCs) that originated at the apex and migrated to the
cecum-colonic junction at a velocity of 13 +/- 1.3 cm/min. The amplitude of
cecal GMCs was 1.82 +/- 0.26 and 3.37 +/- 0.39 times larger than that of
contractions during ileal and colonic motor complexes, respectively (P less
than 0.05). The mean duration and period of cecal GMCs were 45 +/- 4 s and
61.4 +/- 14.2 min, respectively, in the fasted state and 49 +/- 6 s and
68.5 +/- 13.5 min in the fed state, respectively (P less than 0.05). A
total of 82 cecal GMCs was recorded in 71 h of fasted recording and 94 in
121 h of fed recording. Cecal GMCs were not coordinated with colonic MMCs.
Intravenous motilin, but not morphine, initiated a premature cecal GMC. We
concluded that cecum has a unique motor activity that is different from
that of the colon and the ileum. The strong caudad GMCs of the cecum may
periodically empty cecal contents into the colon.
