Beta adrenergic regulation of the hydrochloric acid secretion

Propranolol induces basal achlorhydria in 30.7% of the patients, decreases significantly the HCl secretion in 42.3%, does not change it in 25% and increases it in 1.9%. After histamine stimulation (Kay test) propranolol decreases HCl in 57% and increases it in 43% of the cases. Propranolol induces a significant decrease of carbon anhydrase in the gastric mucosa. Serum gastrin is not significantly decreased after propranolol treatment. Isoprenaline increases the HCl secretion in all the patients investigated. Propranolol suppresses the effect of isoprenaline in 28.6% of the cases, decreases it in 33%, does not change it in 19% and increases it in 19%. The action of isoprenaline is not influenced by atropine, so the mechanism of action of the beta agonist is non-cholinergic. The gastric juice volume is not changed significantly by the blockage or stimulation of beta receptors. The beta adrenergic nervous system stimulates HCl secretion.