[Dopamine infusion test as a gastric secretion test]

The secretion of gastric acid in the peptic ulcer patients were examined by the dopamine infusion test (DIT). Production of gastric acid was investigated when the patients were treated by 30-minute dopamine infusion of 2 micrograms/kg/min. According to the difference of production of gastric acid, 132 patients were categorized into three groups: 59 Cata-responders, 28 Ana-responders and 45 Non-responders. Cata-responders were the patients whose production was less than 0.2mEq/30 min, Ana-responders, greater than 0.2mEq/30 min and Non-responder less than or equal to 0.2mEq/30 min. Cata- and Ana-responders showed higher gastric acid secretion preoperatively, and higher gastric acid reduction rate after selective proximal vagotomy (SPV) than Non-responder. Cata-responder showed decreased acid output preoperatively and unchanged after SPV with DIT. Ana-responder showed increased acid output preoperatively and decreased after SPV with DIT. Non-responder showed unchanged acid output preoperatively and decreased after SPV. Cata-responder may be depending more on vagus-mediated factor and parietal cell mass. Ana-responder may be depending more on vagus-mediated factor, parietal cell mass and dopaminergic factor. Non-responder may be depending more on gastrin cell mass and less cholinergic influence. From these findings dopamine receptor may exist in the stomach, and DIT seems to be useful in studying pathogenesis of the peptic ulcer and determining treatment for patients with peptic ulcer.