Effect of changes in the intragastric milieu on competence of the gastro-oesophageal region. A study in normal subjects.

Acid-reflux studies were carried out in 10 healthy subjects in the basal state, during continuous infusion of pentagastrin (0.015 mug/kg body-weight) after bolus injection of insulin (0.2 IU/kg bodyweight), and after intragastric instillation of 200 ml hydrochloric acid. Basal gastro-oesophageal sphincter pressure and rise in intragastric pressure on leg raising were measured by means of perfused catheters. The increase of intragastric acidity during infusion of pentagastrin and during insulin-induced hypoglycaemia was not accompanied by changes in the competence of the gastro-oesophageal region. Instillation of hydrochloric acid was followed by a significant enhancement of the reflux tendency. Changes in intragastric pressure-rise were not demonstrated in any of the series of investigation. Gastric acid secretion and its significance at the evaluation of the results of reflux studies by means of pH-measuring equipment has not been clarified in patients. It can therefore reasonably be demanded of future acid reflux studies that details have to be stated with regard to acid secretion, and that these should be taken into account at the assessment of the results of the study.