Mechanism of Cl- translocation across small intestinal brush-border membrane

Cl- translocation across small intestinal brush- border mem-brane. II. Demonstration of Cl--OK exchange and CL- con-ductance. Am. J. Physiol. 242 (Gastrointest. Liver Physiol. 5): G272-G280, 1982.-The mechanisms of Cl- transport across the brush-border membrane from rat small intestine were in-vestigated in vitro in isolated vesicles and in vivo in ileal and jejunal segments. A Cl--OH- exchange mechanism was dem-onstrated in isolated vesicles by observing concentrative Cl-uptake driven by a pH gradient (extravesicular pH less than intravesicular pH). A Cl- conductance pathway was demon-strated by concentrative Cl- uptake driven by a K+ diffusion potential. The K ’ diffusion potential was generated by a K’ concentration gradient in the presence of valinomycin (extra-vesicular K ’ concentration greater than intravesicular K+ con-centration).- Furosemide and stilbene 4-acetamido-4’-isothiocy