Figure 1.

Effects of tau and/or methylene blue (MB) on Ca²⁺-ATPase activity in membranes from human control (HC, ⭘⬤) and Alzheimer’s disease (AD) affected (HAD, △▲) brain samples. Membranes (20 μg) were incubated as previously described without (open symbols) or with (filled symbols) 7.5 nM tau in 1 mL final volume with the assay medium, which also contained 0.01% saponin. Activities were assayed after triggering the reaction with 1 mM ATP followed by the addition of the indicated concentrations of MB. Data are expressed in µmol.min⁻¹.mg⁻¹ protein ±SE of four experiments performed with four preparations. * p < 0.001 vs. control.