Local disorganization of interdigestive migrating complex by perfusion of a Thiry-Vella loop.

In dogs, a 50-cm Thiry-Vella loop was perfused with different glucose solutions (10-60%) and the effect on the interdigestive migrating myoelectric complex was studied. The perfusions did not disrupt the interdigestive pattern outside the loop, but produced a progressive "fall-out" of phase III, related to the concentration of the glucose solution. Quantitative analysis of the spike activity in the loop showed that the interdigestive pattern was partially disrupted by the 10% glucose solutions and that the 50 and 60% glucose perfusions induced a typical fed pattern characterized by short periods of spike activity alternating with short periods of quiescence. It was concluded that 1) perfusion of a Thiry-Vella loop with glucose solutions changes the myoelectrical activity of the loop from an interdigestive to a digestive pattern without interfering with the migrating myopelectric complex outside the loop; and 2) this local disorganization must be mediated by factors interfering with the effector mechanism in the loop.