Transepithelial ion transport across duct cells of the salivary gland
Related Experiment Video
Updated: May 6, 2026

Use of the Ramsay Assay to Measure Fluid Secretion and Ion Flux Rates in the Drosophila melanogaster Malpighian Tubule
Published on: November 25, 2015
1Epithelial Signaling and Transport Section, Molecular Physiology and Therapeutics Branch, National Institute of Dental and Craniofacial Research, National Institutes of Health, Bethesda, MD, USA.
Abstract:
Fluid and electrolyte secretions are vital for all epithelia and when aberrant lead to numerous pathophysiological conditions. Electrolyte transport across epithelia generates the osmotic force for fluid movement and is mediated by several membrane proteins expressed on both apical and basolateral poles of epithelial cells. Sodium and chloride are crucial for regulation of fluid secretion, thus regulating salivary volume. Bicarbonate (HCO3-), on the other hand, is the major pH buffer; hence, aberrant HCO3- secretion is a major factor in diseases such as cystic fibrosis (CF) causing altered mucin hydration and solubilization. Here, the structure-function mechanisms of the major membrane transporters involved in salivary duct electrolyte transport are reviewed focusing on transepithelial movement of Cl(-) and HCO3-.
Related Concept Videos
Reabsorption and Secretion in the DCT and Collecting Duct
The distal...
Transcellular Transport of Solutes
Reabsorption and Secretion in the PCT
Transport mechanisms involving sodium ions (Na+) contribute significantly to solute reabsorption. These mechanisms include symport and antiport processes.
A key example is the...
Tubular Reabsorption and Secretion
Tubular reabsorption is a selective process that starts when the filtrate enters the proximal tubules. It involves substances traveling through the transcellular route (through the tubule cell and peritubular...
Physiology of the Genitourinary System II: Tubular Reabsorption and Secretion
Reabsorption and Secretion in the Loop of Henle

