Electrical activity in the gastroduodenal area—Slow waves in the proximal duodenum a comparison of man and dog

Recordings of electrical activity of the smooth muscle in the first and second parts of the duodenum were made from electrodes implanted under the serosa in 15 human subjects and in 4 dogs. Similar records were obtained from mucosal suction electrodes in 5 men. Slow-wave electrical activity in the duodenum of man had a frequency plateau (mean:11.7±0.13 cycles/min) with a time-dependent phase shift. In the dog, slow waves also formed a frequency plateau in this area of the gut but with a constant phase shift. Both patterns could be modelled by variations of couplings between relaxation oscillators set up on an analog computer.Supported in part by a grant from the Medical Research Council.