Conductive chloride flux across amphibian skin: inhibition by indacrinone and cobalt ion.
When amphibian skin was incubated under conditions in which transepithelial sodium transport was abolished, a conductive transepithelial Cl- flux arose when Cl- was removed from one of the compartments. This flux was matched by short-circuit current and it accounted entirely for transepithelial conductance. Cl- influx was larger than efflux; it was linearly related to the magnitude of transepithelial Cl- concentration difference. When applied to the epithelial surface of the tissue, divalent metal cations such as Co2+, and the ethacrynic acid derivative, indacrinone, reduced rapidly and reversibly both transepithelial Cl- (in)flux and short-circuit current. Frog skin proved to be more sensitive to these inhibitors than toad skin. Further characterization of transepithelial Cl- pathway(s) should benefit from the fact that Cl- across amphibian skin can easily be monitored by the short-circuit current method, and from the availability of agents which inhibit this passive flux rapidly and reversibly.
Beaujean
V
V
Department of Physiology, U.C.L. Medical School, Brussels, Belgium.
Crabbé
J
J
D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002024:Bufo marinus; D002463:Cell Membrane Permeability / Q000187:drug effects; D002712:Chlorides / Q000378:metabolism*; D003035:Cobalt / Q000494:pharmacology*; D004553:Electric Conductivity; D066298:In Vitro Techniques; D007189:Indans / Q000494:pharmacology*; D011893:Rana esculenta; D012867:Skin / Q000187:drug effects / Q000378:metabolism*; D012879:Skin Physiological Phenomena; D012964:Sodium / Q000378:metabolism
D002712:Chlorides; D007189:Indans; D003035:Cobalt; D012964:Sodium; C013352:indacrinone