Inhibitory effect of ouabain and acetazolamide on secretin-stimulated pancreatic exocrine secretion in anaesthetized dog.

1. The effects of ouabain and acetazolamide on the secretion of pancreatic juice stimulated by secretin in anaesthetized dogs were investigated. 2. Intra-arterial injection of ouabain (1-10 micrograms) and acetazolamide (1-10 mg) caused dose-dependent decreases in the volume of pancreatic juice. When both drugs were added together, the inhibitory effects were significantly higher than for each drug alone. 3. The bicarbonate concentration in the pancreatic juice was decreased and the chloride concentration was increased by ouabain and acetazolamide, but sodium and protein concentrations were not modified. 4. The results suggest that the Na+,K+-ATPase and carbonic anhydrase activities play important roles in water and electrolyte secretion, and that ouabain and acetazolamide inhibit secretin-stimulated pancreatic secretion by acting on different systems in the exocrine cells in dogs.