Many types of smooth muscle tissues have now been shown to contain ICC, but with few exceptions the function of these cells is not known and is currently an area of active research. An international society (International Society for ICC, www.isicc.org) has recently been formed to provide a forum to discuss research in ICC in a variety of tissues.
ICC also mediate neural input from enteric motor neurons. Animals lacking ICC have greatly reduced responses to the transmitter, acetylcholine, released from excitatory motor neurons, and to the transmitter, nitric oxide, released from inhibitory motor neurons. Loss of ICC in disease, therefore, may interrupt normal neural control of gastrointestinal (GI) contractions and lead to functional GI disorders, such as irritable bowel syndrome.
ICC also express mechano-sensitive mechanisms that cause these cells to respond to stretch. Stretching GI muscles can affect the resting potentials of ICC and affect the frequency of pacemaker activity.
ICC are also critical in the propagation of electrical slow waves. ICC form a network through which slow wave activity can propagate actively. If this network is broken, then 2 regions of muscle will function independently.