Effects of physiological increases of plasma noradrenaline on gastric acid secretion and gastrointestinal hormones.

It is not known if the increased plasma concentration of noradrenaline in patients with chronic duodenal ulcer disease is a pathogenetic factor or not. The aim of the present study was to investigate if physiologic changes of noradrenaline would evoke any alterations in gastric acid secretion or in the plasma concentration of some gastrointestinal hormones (gastrin, secretin, PP, PYY, and GIP) known to affect gastric physiology. The results show that basal plasma noradrenaline concentration was 1.8 nM and after infusion with noradrenaline at 0.04 or 0.2 nmol/kg/min plasma levels of 2.5 and 4.4 nM were obtained. No appreciable changes could be found in basal or pentagastrin stimulated acid secretion or in any of the gastrointestinal peptides studied. If the elevated plasma noradrenaline concentration observed in duodenal ulcer patients is a pathogenetic factor; it is probable that it interferes with other variables such as blood flow, bicarbonate secretion, or prostaglandin synthesis.