Chronic electrical activity of gastroduodenal area: effects of food and certain catecholamines

¹ Parke, Davis & Company, Research Laboratories, Ann Arbor, Michigan

A method of implanting electrodes for long-term chronic studies in the gastrointestinal tract of dogs was developed. The electrodes are placed without disrupting bowel continuity, content flow, nerve, or blood supply. They record the two waveforms of electric activity of the gastrointestinal tract (basic electric rhythm (BER) and spike potentials), conduction patterns, and display interrelationships between various segments of the tract. The electrodes were used to evaluate the action of epinephrine, levarterenol, and feeding on the antral-duodenal region. Spike potentials which are associated with contractions were eliminated by the drugs in both antrum and duodenum. The catecholamines initially on infusion, produced arrhythmias in the antral BER and some distortion of the duodenal BER. With continued drug infusion, the frequency of the antral BER was either unchanged or slightly reduced, while the two drugs increased duodenal BER frequency. These differences in response to the drugs suggest that the basic mechanisms which control the electrical rhythms differ in the two organs.