FIG. 5.

SS-31 and SS-20 reduced mitochondrial swelling induced by 300 μM MPP⁺ in the presence of 50 μM Ca²⁺ and Pi. Mitochondrial swelling was measured by decrease in absorbance at 540 nm. Addition of MPP⁺ alone dose-dependently increased mitochondrial swelling (A). The light gray line indicates no MPP⁺ added. The swelling induced by 300 μM MPP⁺ was prevented by addition of 50 μM SS-31 (B) or 50 μM SS-20 (C).