Effects of 4-acetamido-4'-isothiocyano-2,2-disulfonic stilbene on ion transport in turtle bladders.

The disulfonic stilbene (4-acetamido-4'-isothiocyano-2,2'-disulfonic stilbene) is found to be more potent than acetazolamide as an anion transport inhibitor in the turtle bladder, but less potent than acetazolamide as a carbonic anhydrase inhibitor. The anion-dependent (HCO-3,Cl-) moiety of the short-circuiting current is eliminated by 4-acetamido-4'-isothiocyano-2,2'-disulfonic stilbene, but only after its addition to the serosal bathing fluid. Whereas 4-acetamido-4'-isothiocyano-2,2'-disulfonic stilbene has no effect on Na+ transport across the bladder, it is more potent than ouabain as an inhibitor of microsomal (Na+ + K+)-ATPase of both turtle bladder and eel electric organ.