Effect of oral and intravenous propantheline bromide on pentagastrin-stimulated canine gastric secretion.

The gastric antisecretory efficacy of propantheline bromide (PB) as a function of the route of administration was studied in dogs equipped with chronic gastric fistulae. Sectetion was near-maximally stimulated by continuous intravenous (i.v.) infusion of pentagastrin. PB was administered either intragastrically (i.g.) or intravenously as a single bolus dose at the steady-state plateau of gastric secretion. The administration of PB produced a dose-dependent inhibition of gastric secretion (water and acid output). Gastric acid concentration was not appreciably inhibited by PB. The dose-response (inhibition of acid output) curves for i.g. and i.v. administered PB were parallel. The potency (fiducial limits) of i.v. relative to i.g. administration was found to be 0.002 (0,0006--0,0051) when the i.v. value was taken as unity.