Figure 4. The concept ofpacemaking in the gastrointestinal tract. (a) A diagrammatic representation of an ICC network in intimate contact with smooth muscle cells. (b) Spontaneous voltage oscillations recorded from isolated ICC of mouse small intestine. High amplitude oscillations arose sharply from the resting membrane potential at regular intervals. (From Am JPhysiol 1999;277:G409-23 with permission from the American Physiological Society - ref 53).