Influence of gastric acid secretion on interdigestive gastric motor activity and serum motilin in the elderly.

The purpose of this study is to investigate the influence of gastric secretion on the interdigestive gastric motor activity and related serum motilin variations in elderly subjects. The study was carried out on two groups of elderly subjects: one with achlorhydria or marked hypochlorhydria due to chronic atrophic gastritis and the other with normal acid secretion. A group of nonelderly subjects with normal acid secretion was also examined as control. Gastric motility was studied manometrically and serum motilin was measured by radioimmunoassay on blood samples taken every 15 min during the entire motor recording period of 200-300 min. Both groups of elderly subjects showed (1) alterations in interdigestive gastric motility and (2) serum motilin which was steadily high without the normal cyclic fluctuations. These studies suggest that the alterations in gastric motor activity and serum motilin in aged subjects are not related to the acid secretory capacity of the stomach. Other factors, such as alterations in the neurohormonal control system of gut motility, should be considered in the genesis of these age-related disorders.