Figure 3.
![Figure 3. Block by divalent cations. (A) Macroscopic I-V curve of an outside-out patch coexpressing MEC-4d/10d, MEC-2, and MEC-6 exposed to varying Ca2+ concentrations. (B) Dose–response curves for blockade by Ca2+ and Mg2+ at −100 mV. The smooth curve is fit to the average values assuming a Hill coefficient of 1: \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(I{=}I_{\mathrm{max}}(1{+}[X^{2{+}}]/K_{i}{'})^{{-}1}\) \end{document}. Measured Ki' was 12.9 mM for Ca2+, 7.0 mM for Mg2+. (C) Apparent Ca2+ inhibition constant, Ki' as a function of auxiliary subunits. Vhold = −60 mV. (D) Voltage dependence and variation of block affinity. Each line represents a single patch, with Ki' measured at −60 and −100 mV.](https://cdn.rupress.org/rup/content_public/journal/jgp/131/6/10.1085_jgp.200709910/7/jgp_200709910_gs_fig3.jpeg?Expires=1768360272&Signature=h~dlRB6bHkkCsiEGu~jKGeMxKyP9S2LQDhoP368NPNI~MZ9t0usfJ40Wzz6FwGCvyn80sxtGToYdRVq2VC0s4GG6zzrbbsPyh8t438CpRyPhknwiZaRvTPv0zkWfI0s79EaPwo4B5tXxS~5bgh2A4hTkcw-yQ8LOiyNQtpYhG-GQNoT44~OKnZ8PlLytfasJh4zYh0vjg9zTFdPjfg8oAO9ycPSDP~L-PTARQrDd8PXs1jhohOJ8td7EV0CXiBE1M4MUCtqA8rmyXVAtR8MryIO63NpegYNoKMacyD0qHjH~vWob~KnUNH~lhq0tWtLvrVrNmgYROhVNeT-kLKeXwQ__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
Block by divalent cations. (A) Macroscopic I-V curve of an outside-out patch coexpressing MEC-4d/10d, MEC-2, and MEC-6 exposed to varying Ca2+ concentrations. (B) Dose–response curves for blockade by Ca2+ and Mg2+ at −100 mV. The smooth curve is fit to the average values assuming a Hill coefficient of 1: \(I{=}I_{\mathrm{max}}(1{+}[X^{2{+}}]/K_{i}{'})^{{-}1}\) . Measured Ki' was 12.9 mM for Ca2+, 7.0 mM for Mg2+. (C) Apparent Ca2+ inhibition constant, Ki' as a function of auxiliary subunits. Vhold = −60 mV. (D) Voltage dependence and variation of block affinity. Each line represents a single patch, with Ki' measured at −60 and −100 mV.
