Regional gastric blood flow and acid secretion during histamine H2 receptor blockade in cats.

Experiments were performed in anesthetized cats. Tissue blood flow and cardiac output were measured by means of labeled microspheres. Cimetidine did not affect gastric blood flow at basal conditions. Pentagastrin stimulation more than doubled corpus-fundus mucosal blood flow (MBF). Cimetidine reduced pentagastrin-stimulated corpus-fundus MBF and acid output towards basal level. Recovery of acid secretion after inhibition by a bolus dose of cimetidine occurred without a corresponding restoration of MBF. Neither pentagastrin nor cimetidine significantly altered antrum MBF or muscularis blood flow. The study demonstrates that cimetidine reduces the ratio between pentagastrin-stimulated acid secretion and corpus-fundus MBF by lowering secretion considerably more than the corresponding MBF.