The existence of possible local mediators of the inhibitory effect of neurotensin on gastric acid secretion has not been determined. We perfused rats intragastrically with warmed saline and stimulated acid secretion with intravenous pentagastrin, 32 mug/kg/hr, and found that anesthesia with pentobarbital resulted in marked inhibition of acid secretion by intravenous neurotensin; however, anesthesia with urethane prevented this inhibitory effect of neurotensin from occurring. In addition, we found a significant increase in somatostatin-like immunoreactivity in portal venous blood during neurotensin infusion in pentobarbital-anesthesized rats. Neither neurotensin nor pentagastrin infusion modified gastric luminal somatostatin-like immunoreactivity after either pentobarbital or urethane, and rats anesthesizex with urethane did not show an increase of somatostatin-like immunoreactivity in portal venous blood during neurotensin infusion. These results suggested that somatostatin-like immunoreactivity, released into the portal circulation, was necessary for exogenous neurotensin to inhibit pentagastrin-stimulated gastric acid secretion under those conditions in anesthesized rats.
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Pharmacology, Toxicology and Pharmaceutics(all)