[Effect of SITS (4-acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic acid) on the transport of chloride through the isolated skin of Rana esculenta].

The effect of SITS (6 . 10(-4)M on transepithelial potential (E) and short circuit current (I) of isolated frog skin has been studied either using Ringer or Cl- -depleted Ringer in the outside bathing solution. SITS affects the transepithelial potential (E) and the short-circuit current (I) only if normal Ringer is used and SITS is added in the outside bathing medium. The existence of a negative exchanging-charge carrier on the external membrane of the epithelial cells is postulated. This mechanism could be a step of the actively transported Cl- ions.