Pyloric motor activity and function with special reference to pyloroplasty after vagotomy

Abstract

Using adult mongrel dogs, pyloric motor activity and gastric emptying observed by phototransducer (P.T.) under anesthesia and by strain gage transducer (S.G.T.) under consciousness. Pyloric motor activity and function were investigated in the dogs with distorted pylorus after instorations of Daclon tube, pyloric resection and pyloric stenosis. The pyloric sphincter responses to gastrin, pancreozymin, secretin, glucagon, atropine, morphine, naloxone and enkephalin administrated intravenously were observed. Gastroduodenal motor activity in relation to the changes of gastrointestinal hormone levels were measured before and after truncal vagotomy (TV) and selective proximal vagotomy (SPV) with or without pyloroplasty. Results are summarized as follows; 1. The pyloric motility recorded by P.T. was well correlated with the contractile activity recorded by S.G.T. under the anesthesia, although the pylorus was never completely closed and showed tonic movements. 2. The pyloric motor activity under the consciousness was different from gastric and duodenal motor activity. 3. After SPV, the gastrin responses to the test meals were significantly increased so that the pyloric motility was disturbed. The fact mentioned above, the pyloric functional disorder after the SPV was partly due to the hypergastrinemia. Pyloroplasty for the SPV inhibited the serum gastrin level. It was suggested that the pyloroplasty for the SPV was necessary to prevent possible hypergastrinemia after SPV.