ABSTRACT
The tissue was found to have a serosa negative potential, and shortcircuit currents equivalent to the net Cl transport.
A significant part of the Cl uptake was Na dependent and a similar fraction of the Na uptake was Cl dependent.
Short-circuit current and uptake of both ions were inhibited by loop diuretics and analogues. 4. Isc and p.d. were abolished by ouabain.
The observations are consistent with the idea of a coupled NaCl entry into the cell, using the energy inherent in the Na gradient; Na being pumped out of the cells by the Na pump and followed electrically by Cl−. Net chloride transport and the serosa negative potential would be a consequence of the permselective properties of the junctions allowing Na but not Cl to recycle back to the mucosal solution.
