Abstract
1. In frog atrium, Cs ions block both the inward rectifieri K1 and the carbachol induced K currenti Cch. 2. Bothi K1 andi Cch display a high affinity for Cs with a K0.5 of 4×10−5 M fori k1 and of 8×10−5 M fori Cch atV=−50 mV. 3. Block of bothi K1 andi Cch is strongly voltage dependent. When fitted by the block model of Woodhull (1973), δ is >1 for the two currents. 4. From these similarities, action of Cch on frog atrium K permeability could be interpreted as a modification ofi K1.
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This work has been supported by CNRS (L.A. 244) and by INSERM (C.R.L. 815023)
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Argibay, J.A., Dutey, P., Ildefonse, M. et al. Block by Cs of K currenti K1 and of carbachol induced K currenti Cch in frog atrium. Pflugers Arch. 397, 295–299 (1983). https://doi.org/10.1007/BF00580264
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DOI: https://doi.org/10.1007/BF00580264