ICC are unique cells that either have intrinsic pacemaker activity, or can perform stimulus-induced pacemaking they act as networks and this network is connected to inhibitory and excitatory intrinsic and extrinsic nerves that influence the ICC network.
Interstitial cells of Cajal (ICC) are part of the control system that orchestrates and regulates a diverse set of motor patterns in all parts of the gut to facilitate absorption, transit, neural innervation, stretch sensation, and bacterial homeostasis. Slow waves in circular muscle are dependent on the integrity of the junction between the submucosa and the innermost circular layer. Slow waves are not generated in longitudinal muscle. Exposure of the mucosal surface of isolated circular muscle to a hypertonic solution of KCl abolished slow waves, while exposure of the serosal surface to the same concentrations had no effect. Removal of the submucosa from the circular muscle surface abolished slow waves recorded from both isolated circular muscle and the intact specimen. Slow waves were recorded extracellularly from circular and longitudinal muscle when the two layers formed the intact muscle wall they were also recorded from isolated circular muscle, but not from isolated longitudinal muscle. Intracellular electrical activity was also studied in intact muscle, in isolated circular muscle, and in isolated longitudinal muscle. Extracellular electrical activity was recorded in vitro from strips of intact muscle wall and from isolated circular and longitudinal muscle using either multiple electrodes applied to one side of the specimen or two electrodes applied simultaneously to opposite sides of the tissue. The objectives of this work were to determine the origin of slow wave activity in the canine colon, to examine the slow wave characteristics in the circular and longitudinal muscle layers, and to examine the roles played by each of these layers in the generation of this activity.