Figure 4.

The effect of Aβ oligomers on the conductance induced by nonactin. (A) The bottom trace shows the current measured at 150 mV induced by Aβ oligomers. Additions of Aβ oligomers and the resulting concentrations (μM) are shown by the arrows. The top trace shows a similar experiment performed in the presence of 10⁻⁸ M nonactin but with only two additions of amyloid, corresponding to the two lowest concentrations in the bottom trace. The bath solution contained 10 mM KCl in both cases, lipid composition was PC/PS (1/1, molar). (B) Normalized nonactin conductance and bare bilayer conductance as a function of Aβ oligomer concentration. Conductance at a given Aβ oligomer concentration divided by the conductance at 0 Aβ oligomer concentration is plotted against Aβ oligomer concentration. The initial conductance of the nonactin-K⁺ membrane was >200 times that of bare bilayer. Note that the dose–response curve for nonactin is essentially a multiple of the bare bilayer dose–response curve.