Abstract
In cell-free patches from cultured neonatal rat cardiocytes, the cytosolic presence of GTP-γ-S (100 µmol/l) or GDP-\-S (100 µmol/1) activated K(ATP) + channels. GTP-γ-S required cytosolic Mg++, suggesting that an activated G-protein causes the increase in open probability. The great variations of the channel response to GTP-γ-S and GDP-\-S indicates that cardiac K(ATP) + channels represent a heterogeneous family.
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Correspondence to: M. Kohlhardt
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Benz, I., Kohlhardt, M. Differential sensitivity of cardiac K(ATP) + channels to guanine nucleotides — evidence for a heterogeneous channel population. Eur Biophys J 21, 299–302 (1992). https://doi.org/10.1007/BF00185124
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DOI: https://doi.org/10.1007/BF00185124