ReviewsThe Physiology and Pathophysiology of Pancreatic Ductal Secretion The Background for CliniciansPallagi, Petra PhD*; Hegyi, Péter MD, PhD, DSc*†; Rakonczay, Zoltán Jr MD, PhD, DSc* Author Information From the *First Department of Medicine, University of Szeged; and †Hungarian Academy of Sciences–University of Szeged Translational Gastroenterology Research Group, Szeged, Hungary. Received for publication September 3, 2014; accepted March 2, 2015. Reprints: Zoltán Rakonczay, MD, PhD, DSc, First Department of Medicine, University of Szeged, PO Box 427, H-6701 Szeged, Hungary (e-mail: [email protected]). Our research is supported by Hungarian National Development Agency grants (TÁMOP-4.2.2.A-11/1/KONV-2012-0035, TÁMOP-4.2.2-A-11/1/KONV-2012-0052, TÁMOP-4.2.2.A-11/1/KONV-2012-0073), the Hungarian Scientific Research Fund (NF105758), the Hungarian Academy of Sciences (MTA-SZTE Momentum grant, LP2014-10/2014), and the European Union and the State of Hungary, cofinanced by the European Social Fund in the framework of TÁMOP 4.2.4.A/2-11-1-2012-0001 National Excellence Program. The authors declare no conflict of interest. Pancreas 44(8):p 1211-1233, November 2015. | DOI: 10.1097/MPA.0000000000000421 Buy Metrics Abstract The human exocrine pancreas consists of 2 main cell types: acinar and ductal cells. These exocrine cells interact closely to contribute to the secretion of pancreatic juice. The most important ion in terms of the pancreatic ductal secretion is HCO3−. In fact, duct cells produce an alkaline fluid that may contain up to 140 mM NaHCO3−, which is essential for normal digestion. This article provides an overview of the basics of pancreatic ductal physiology and pathophysiology. In the first part of the article, we discuss the ductal electrolyte and fluid transporters and their regulation. The central role of cystic fibrosis transmembrane conductance regulator (CFTR) is highlighted, which is much more than just a Cl− channel. We also review the role of pancreatic ducts in severe debilitating diseases such as cystic fibrosis (caused by various genetic defects of cftr), pancreatitis, and diabetes mellitus. Stimulation of ductal secretion in cystic fibrosis and pancreatitis may have beneficial effects in their treatment. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.