AJP - Gastrointestinal and Liver Physiology, Vol 238, Issue 4 321-G325, Copyright © 1980 by American Physiological Society
Effect of deoxycholic acid on colonic motility in the rabbit
W. J. Snape Jr, S. Shiff and S. Cohen
The purpose of the study was to determine the effect of the bile salt,
deoxycholic acid, on colonic myoelectrical and contractile activity
recorded from a loop of proximal colon in the anesthetized rabbit.
Myoelectrical activity was recorded from bipolar electrodes attached to the
serosal surface of the proximal colon. Contractile activity of the circular
smooth muscle was measured with a strain gauge attached in the circular
direction on the serosal surface of the colonic loop. The colonic slow wave
frequency was 12.5 +/- 1.1 cycles/min. The slow wave frequency throughout
the loop was homogeneous with a low coefficient of variation of the slow
wave frequency (5.8 +/- 0.3). There were spike potentials superimposed on
78.1 +/- 3.4% of the slow waves. The addition of 8 or 16 mM deoxycholic
acid did not change the slow wave or spike activity. However, deoxycholic
acid stimulated a dose-dependent increase in migrating action potential
complexes. These complexes were associated with a forceful contraction of
the circular smooth muscle that propelled luminal contents in the direction
of the burst. Deoxycholic acid also stimulated an increase in luminal fluid
content.
