Effects of Acid in Stomach and Duodenum upon the Gastric Myoelectrical Activity in Man

Abstract

The period of the pacesetter potentials (PP) in the normal human stomach was studied when infusing HCl (75 mEq/l) or saline in the stomach or duodenum. When a 350-ml volume of saline was infused into the stomach, an 11 % increase of the PP period was observed. With 350 ml of acid solution, the maximum increase was 40%. This occurred 8 min after the onset of infusion, at the moment when the serum gastrin level was significantly lowered. When the acid solution was infused into the duodenum, a flow rate of acid dependent increase of the PP period occurred (43% with 4 ml/min). Saline induced no change. A single intravenous injection of secretin (0.5 U/kg) induced an increase in the PP period whose maximum (35%) occurred 4 min after the injection. The results suggest that gastric myoelectrical activity may be affected by a hormonal regulation in which endogenous secretin and gastrin would determine opposite responses.

Effect of some gastrointestinal hormones on motor and electrical activity of the digestive tract in the conscious cat

“…This species difference might be secondary to acid secretion, as pointed out by Wingate et al (1978). BER frequency has been shown to be sensitive to acid in man (Couturier et al 1973). However, under our experimental conditions, gastric juice was continuously collected by a gastric cannula placed in the declivitous part of the fundus.…”