Electromyography of the intestines by the intra-intestinal method.

A U-loop bipolar collar electrode was devised for the use in electromyography of the intestines via the mouth or rectum. The findings in animal and clinical experiments were presented. The pattern of action potentials obtained by the intrƒ¿-intestinal method using this U-loop bipolar collar electrode was almost the same as that recorded by the ordinary extra-intestinal method with laparotomy. With the extra-intestinal method, the maximum amplitude was 1.2 mV, average amplitude 0.3 mV, burst duration 1.2-1.5 see, spike number 10-11, and burst interval 12.8 see, while with the intrƒ¿-intestinal method, the maximum amplitude was 0.66 mV, average amplitude 0.34 mV, burst duration 1.2-1.5 see, spike number 10-11 and burst interval 12.8 sec. The pattern of action potentials of the small intestine obtained by swallowing the electrode and that of the large intestine obtained rectally were found to be quite similar to those at the same sites recorded by the extra-intestinal method.