about the control of smooth muscle motility

The motor apparatus that produces gastrointestinal motility is composed of at least three critical elements: nerves, interstitial cells of Cajal (ICC) and smooth muscle cells. The latter are the motor element, which, acting alone, are incapable of producing co-ordinated motility.
The first level of coordination comes from intrinsic electrical activity, known as slow waves. These originate within specialised 'pacemaker regions' populated by ICC, which generate spontaneous slow wave activity. These cells have unique intracellular timing mechanisms and ionic conductances, and are electrically coupled to each other and to neighbouring smooth muscle cells via gap junctions. Slow waves are generated in ICC, actively propagate in ICC networks, and conduct passively in smooth muscle cells.

Kenton Sanders (Reno, Nevada) 2005