Plasma secretin level and exocrine pancreatic secretion in response to intraduodenal infusion of 1-phenyl-1-hydroxy-n-pentane and HCl by using a new four lumen tube.

We have designed a four lumen tube which has enabled us to aspirate duodenal juice while infusing endogenous stimuli into the lower part of duodenum. Exocrine pancreatic secretion and plasma immunoreactive secretin (IRS) levels have been simultaneously observed in response to intraduodenal infusion of 1-phenyl-1-hydroxy-n-pentane (PHP) and 0.1 N HCl in normal subjects, patients with diabetes mellitus and patients with chronic pancreatitis by use of this tube. (1) Pancreatic flow rate and bicarbonate concentration were found to increase to twice those of basal levels and plasma IRS levels rose significantly after infusion of PHP or HCl in normal subjects. The same tendency was observed in patients with diabetes mellitus. (2) Exocrine pancreatic secretion did not change after infusion of PHP or HCl in patients with chronic pancreatitis. Pancreatic flow rate, bicarbonate concentration and amylase output were significantly low in patients with diabetes mellitus. (3) Pancreatic flow rate and bicarbonate concentration incresed to about twice those of basal levels after both PHP and HCl infusion. On the other hand, although pancreatic amylase output increased significantly after infusion of HCl as compared with basal secretion, it did not change after infusion of PHP. It appeared reasonable to conclude that PHP is a morespecific substance for releasing secretin than HCl.