Inflammation Reduces Mucosal Secretion of Hydrogen Ions and Impairs Concentrating Function and Luminal Acidification in Feline Gallbladder

Abstract

Background: The gallbladder mucosa normally absorbs fluid and secretes H⁺ ions. The fluid secretion in inflamed gallbladders is induced by prostaglandins and mediated by intramural vasoactive intestinal peptide (VIP)-ergic nerves. Methods: The influence of inflammation on gallbladder mucosal function was studied in cats. Results: In control animals there was acidification of the gallbladder contents due to secretion of H⁺ into the lumen. In animals with inflamed gallbladders this acid secretion was reduced; there was secretion of HCO₃ and no evident acidification of the gallbladder contents. Injection of VIP antiserum or indomethacin restored H⁺ secretion and inhibited HCO₃⁻ and fluid secretion by the inflamed gallbladder mucosa. An impaired acidification of the gallbladder contents due to mucosal inflammation may reduce the solubility of calcium salts in gallbladder bile and increase the risk of their precipitation in the lumen. Conclusion: Mucosal inflammation reduces H secretion and impairs acidification of the gallbladder contents.

Key Words:

• Amiloride
• gallbladder
• HCO₃ secretion
• H⁺ secretion
• mucosal fluid transport
• vasoactive intestinal peptide
• vasoactive intestinal peptide antiserum