Xenbase Image ID: 150460

Figure 1. Comparing the biophysical properties of Ca-α1T and rat Cav3.1.(a) (Left) Representative current traces through Ca-α1T and Cav3.1 expressed in Xenopus oocytes. In 10 mM Ba2+, currents were elicited by depolarizing 10 mV step pulses (−70 mV to +40 mV) from a holding potential of −90 mV. (Right) I–V relationships of Ca-α1T and Cav3.1. Peak currents for each oocyte were normalized to the maximum current. Percent amplitudes from oocytes expressing Ca-α1T (○) or Cav3.1 (⌜) plotted against test potentials and fitted with the Boltzmann equation. (b) (Left) Steady-state inactivation measured during voltage steps to −20 mV after 10 s prepulses to potentials between −100 mV and −40 mV. (Right) Voltage-dependent activation and steady-state inactivation curves of Ca-α1T (○, ●) and Cav3.1 (⌜, ■) fitted to the Boltzmann equation. (c) The activation (τact) and inactivation (τinact) time constants for Ca-α1T (○) and Cav3.1 (⌜) obtained by fitting the current traces to double exponentials. (d) Voltage-dependent deactivation of Ca-α1T in HEK-293 cells. Tail currents elicited by step pulses to −20 mV for 10 ms, followed by re-polarizing potentials (−120 mV to −50 mV). Deactivation time constants were obtained by fitting the traces to a single exponential and plotted against re-polarizing potentials. (e) ICa/IBa ratios of Ca-α1T and Cav3.1. (Left) Representative current traces through Ca-α1T and Cav3.1 measured in 10 mM Ba2+ or 10 mM Ca2+ elicited by 10 mV step pulses from a holding potential of −90 mV. Ba2+ currents are black; Ca2+ currents are grey. (Middle) I–V relationships of Ca-α1T (○, ●) and Cav3.1 (⌜, ■) in 10 mM Ba2+ (open) or 10 mM Ca2+ (filled). (Right) Peak current ratios (ICa/IBa) and relative slope conductance (GMaxCa/GMaxBa) for Ca-α1T and Cav3.1. Student’s t-test, **p < 0.01, ***p < 0.001. (f) Nickel inhibition sensitivity of Ca-α1T and Cav3.1. (Left) Representative current traces of Ca-α1T and Cav3.1 at various Ni2+ concentrations. (Right) Dose-response curves indicating Ni2+-dependent inhibition of Ca-α1T (○) and Cav3.1 (⌜). Data are presented as means ± s.e.m. Image published in: Jeong K et al. (2015) Copyright © 2015, Macmillan Publishers Limited. This image is reproduced with permission of the journal and the copyright holder. This is an open-access article distributed under the terms of the Creative Commons Attribution license Larger Image Printer Friendly View

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