Immunological blocking of exogenous and endogenous secretin in the dog.

In mongrel dogs with chronic gastric and duodenal fistula the biological activity of secretin on exocrine pancreatic secretion could be blocked by preincubating the secretin injected with rabbit antisecretin antibody. In addition, the activity of endogenous secretin released by acid was markedly reduced by application of antibody. Since no such effect was observed after testmeal stimulation, secretin is most probably not released in a significant amount by the liquid meal used in this experiment.