Brain regulation of gastric acid secretion in rats by neurogastrointestinal peptides.

Brain alteration of catecholaminergic, serotoninergic, dopaminergic, gabaergic and cholinergic pathways by intracisternal injection of agonists, antagonists or specific neurotoxic drugs did not significantly affect gastric acid secretion in 2 hr pylorus-ligated rats. In contrast, several neuropeptides were found to be very potent in influencing gastric secretion when administered intracisternally but not when given intravenously. Bombesin-like peptides, opioid peptides and arginine vasopressin acted within the brain to inhibit gastric acid secretion through yet unknown neurohumoral pathways, whereas TRH and some somatostatin analogs elicited brain stimulation of gastric acid output through vagal-dependent mechanisms. These observations have led to the concept that some specific neuropeptides may be important chemical messengers involved in physiologic brain processes regulating gastric acid secretion, and appear as new chemical probes to further investigate the brain-gut relationship.