Effect of vagotomy on the response of gastric myoelectrical activity to glucagon and food.

The myoelectrical activity of the gastric antrum was measured in 13 patients using intraluminal suction electrodes. In 3 patients with intact vagi, intravenous injection of glucagon 5 mug/kg and 10 mug/kg resulted in periods of increased frequency of gastric slow waves and also periods of inhibition. These findings persisted after highly selective vagotomy (7 patients) and were abolished by truncal vagotomy (3 patients). In each of 4 dogs, six silver/silver chloride electrodes implanted under the serosa were used to record the myoelectrical activity of the stomach and duodenum and its response to a meal of 450 gm of meat. Coordination of bursts of spike activity superimposed on the slow waves was significantly diminished after truncal vagotomy but not after highly selective vagotomy. These results confirm that changes in myoelectrical activity after vagotomy are related to the extent of vagal denervation.