Minute rhythm of electrical spike bursts of the small intestine in different species.

Electrical activity of propagating spike bursts recurring at minute intervals was recorded from the small intestine by chronically implanted electrodes in the rabbit, cat, dog, sheep, and pig. This "minute rhythm" has been recorded previously from the intact human small intestine. It occurs in the jejunum with a period duration of 0.5-2.0 min in all species examined. The minute rhythm was accompanied by pressure waves propagating over a short distance, and the activity was most prominent before the onset of phase III of the myoelectric complex. The minute rhythm was activated by the infusion of saline in the jejunum, and it may possibly reflect a normal mechanism for the transport of fluid content.