Xenbase Image ID: 121204

Figure 1. . External TEA block of Shaker K+ channels. (A) TEA block in K+ solutions (5 mM external K+//135 mM internal K+). (Top) Raw current records obtained with step changes in membrane potential from −70 mV to the indicated voltages. Lower record of each pair recorded in the presence of 20 mM TEA. Superimposed on each set of records is the current at the indicated voltage recorded from an uninjected oocyte illustrating the lack of any significant endogenous currents. The current records have not been leak corrected- the small current from the uninjected oocyte is likely through the ∼7 GΩ seal resistance. (Main) Fraction of channel current block by external TEA at −10 (□) and 70 mV (•), respectively. Lines are fits of Eq. 1 to the data with Kapp values of 12.3 ± 0.81 and 25.2 ± 1.4 mM at −10 and 70 mV, respectively. (B) TEA block in Rb+ solutions (5 mM external Rb+//135 mM internal Rb+). (Top) Raw current records obtained with step changes in membrane potential from −70 mV to the indicated voltages. Lower record of each pair recorded in the presence of 20 mM TEA. (Main) Fraction of channel current block by external TEA at −10 (□) and 70 mV (•), respectively. Lines are fits of Eq. 1 to the data with Kapp values of 10.9 ± 0.74 and 12.5 ± 1.2 mM at −10 and 70 mV, respectively. Image published in: Thompson J and Begenisich T (2003) Copyright © 2003, The Rockefeller University Press. Creative Commons Attribution-NonCommercial-ShareAlike license Larger Image Printer Friendly View

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