Figure 6.

Effects of intracellular acidosis and alkalosis on the initial Δ[Mg²⁺]_i/Δt in normally energized cells. (Left) A record taken from a Mg²⁺-loaded cell. After Mg²⁺ loading, Mg²⁺ efflux was induced by extracellular 140 mM Na⁺, as shown at the top. Superfusion solutions also contained EIPA throughout the run (see text). Application and removal of NH₄Cl are indicated by a horizontal bar. The least-squares fitted lines for data points 30–150 s after solution exchange are drawn in solid, and values of the initial Δ[Mg²⁺]_i/Δt estimated from the slopes are indicated near the traces. (Right) Summary of relative Δ[Mg²⁺]_i/Δt (see text for definition) during intracellular alkalosis and acidosis induced by addition and removal of NH₄Cl (4 cells). Values for normal pH were obtained in separate experiments without NH₄Cl application (6 cells). Columns represent mean ± SE. ^∗p < 0.05 versus normal pH. NS, not significantly different from normal pH.