Contribution to the study of hormonal regulation of pancreatic secretin in the rabbit

Abstract

Secretion of pancreatic juice in the rabbit and its control by gastrointestinal hor­ mones was studied. The influence of these hormones on bile secretion was also briefly analyzed. Animals were anaestethized with urethane; femoral vein was cannulated for injection of hormones and carotid artery to record blood pressure; after a mid-line incision, pylorus was ligated and bile and pancreatic ducts cannulated.

Secretion of pancreatic juice and bile were constant and high. Flow of pancreatic juice could be increased up to ninefold with secretion (1 U./kg), threefold with pancreo­ zymin (10 U./kg) and 2.5 times with pentogastrin (10 /xg/kg). The threshold dose of secretin was 0.01 U./kg and that of pancreozymin 0.5 U./kg. Secretin decreased the enzyme content of pancreatic juice, and pancreozymin and pentogastrin highly increased it.

Secretin (1 U./kg) and pancreozymin (1 U./kg) slightly increased the flow of bile. Pancreozymin (10 U./kg) was a powerful stimulus on bile secretion, increasing both, flow and bile salts content.