Passive Cl- Currents in Toad Skin: Potential Dependence and Relation to Mitochondria-Rich Cell Density
In tight epithelia, like amphibian skin, the net flow of Cl- ions is predominantly passive and reflects the electrochemical potential gradient across the skin. In the present paper, we shall discuss the dependence of the Cl- current on the transepithelial potential difference. Our hypothesis is that the potential provides not only the driving force for the Cl- flux, but controls the Cl- permeability as well. Evidence is also presented that the passive Cl- pathway is localized to a special cell type, the mitochondria-rich cells. Modes of Cl- permeability regulation, which have been discussed in the literature, are briefly reviewed.
KeywordsPermeability Urea Eter Theophylline Furosemide
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