Hh. Ussing et F. Lind, TRAPPING OF CS-134(-SKIN EPITHELIUM AS A FUNCTION OF SHORT-CIRCUIT CURRENT() IN FROG), Kidney international, 49(6), 1996, pp. 1568-1569
In the sodium/potassium pump of the isolated frog skin epithelium, Cs-
134(+) can to a certain degree replace potassium. If Cs-134(+) in almo
st a carrier-free amount is added to the solution bathing the inside o
f the frog skin in an Ussing chamber, there will be an uptake of Cs-13
4(+) into the epithelium cells which is proportional to the short circ
uit current. Transepithelial flux of Cs-134(+) in leaky epithelia, for
instance small intestine and frog skin glands, indicates a paracellul
ar pathway. The consequences of these findings for the recycling-theor
y are discussed.