ductal cells refer to cells lining the pancreatic duct

Pancreatic duct

The pancreatic duct, or duct of Wirsung , is a duct joining the pancreas to the common bile duct to supply pancreatic juices which aid in digestion provided by the "exocrine pancreas"...

 and are responsible for production of bicarbonate-rich secretion. Ductal cells are stimulated by the hormone secretin

Secretin

Secretin is a hormone that controls the secretions into the duodenum, and also separately, water homeostasis throughout the body. It is produced in the S cells of the duodenum in the crypts of Lieberkühn...

 and are responsible for maintenance of the duodenal pH and prevention of duodenal injury from acidic chyme. Ductal cell mix their production with acinar cell's to make up the pancreatic juice

Pancreatic juice

Pancreatic juice is a liquid secreted by the pancreas, which contains a variety of enzymes, including trypsinogen, chymotrypsinogen, elastase, carboxypeptidase, pancreatic lipase, and amylase....

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