Sodium and chloride transport across the rumen epithelium of cattle in vitro: effect of short‐chain fatty acids and amiloride

Abstract

Isolated mucosal sheets of cattle rumen were studied in vitro in Ussing chambers using a computer‐controlled voltage clamp. Unidirectional fluxes of Na+ and Cl‐ were measured in standard (short‐chain fatty acid (SCFA)‐free) or SCFA‐containing Ringer solution under zero voltage clamp conditions. Net NaCl absorption was observed under zero voltage clamp conditions, was stimulated by SCFAs and was not reduced by 1 mmol l‐1 amiloride, although short‐circuit current was significantly reduced by this concentration of the blocker. A constant coupling ratio of Na+ and Cl‐ absorption was observed. © 1994 The Physiological Society