Comparison of Juice Obtained during Duodenal Aspiration and Cannulation of the Main Pancreatic Duct after Stimulation with Exogenous Secretin in Man

The exocrine pancreatic secretion obtained by endoscopic cannulation was compared with that obtained by a conventional duodenal tube after exogenous secretin. The flow rate, bicarbonate output, and amylase output in response to secretin was larger during duodenal aspiration than when collecting during endoscopic cannulation. The majority of samples collected from the duodenum contained bile, whereas those from the pancreatic duct were, with few exceptions, colourless. In all patients the bicarbonate concentration was lower in the duodenal aspirate than in the pancreatic juice. In 5 of the 7 patients, however, the concentration of amylase was higher in the duodenal aspirate than in juice collected by endoscopic cannulation. In these patients the quantitative difference found could not therefore solely be explained by non-quantitative collection of juice from the pancreatic duct and/or contamination of bile, intestinal juice, and gastric juice in the duodenum. Augmentation of the response to secretin by the presence of bile and pancreatic juice in the duodenum and inhibition by the endoscopic cannulation of the pancreatic duct are discussed as alternative explanations.