Role of the epithelium in the control of intestinal motility : implications for intestinal damage after anoxia and reoxygenation

A vibration technique was used to dislocate the epithelium from the rat small intestine, in order to study the possible regulatory role of the epithelium on intestinal motility. Complete removal of the epithelium led to a slightly potentiated contraction of the longitudinal smooth muscle by the muscarinic agonist methacholine (pD2 6.5±0.1 vs. 6.2±0.2). The maximal β-adrenergic response expressed relative to the relaxation by 0.5 mM dibutyryl cyclic AMP increased from 55.9±9.0% to 72.6±9.1% by this treatment. Efforts were made to relate these observations to the endothelium-dependent relaxation in blood vessels, but no indication was found for a similar mechanism in the small intestine.