Abstract

The effect of fat and protein meals on the lower oesophageal sphincter pressure was tested in normal subjects using an infused open-tipped manometric system. After ingestion of a minced beef meal, the mean peak pressure at the lower oesophageal sphincter increased 5·8 ± 1·5 mm Hg (± 1 SE). By contrast, ingestion of a corn oil meal resulted in a mean peak decrease of 7·8 ± 1·9 mm Hg. Following the combined minced beef/corn oil meal, mean peak pressure decreased 3·0 ± 2·1 mm Hg. Pentagastrin (3 μg/kg, subcutaneously) resulted in a mean peak increase of 20·6 ± 7·0 mm Hg when given to the subjects in the fasting state, and produced an increase of only 8·4 ± 1·7 mm Hg when given following the fat meal. Finally, after a mean peak decrease in pressure at the lower oesophageal sphincter of 6·8 ± 1·0 mm Hg 15 minutes after the corn oil meal, gastric alkalinization with 30 ml of antacid resulted in a subsequent increase in sphincter pressure of 5·2 ± 1·6 mm Hg. These data indicate: (1) Fat attenuates the effect of endogenous gastrin as well as exogenous pentagastrin stimulation of the lower oesophageal sphincter. (2) Fat-induced incompetency of the lower oesophageal sphincter can be effectively combated by gastric alkalinization in the form of antacids.