A, representative changes in tension generated by a single FDB fibre during fatiguing stimulations at an extracellular of 40 Torr (filled circles) and 5 Torr (open circles) under control conditions. B, force vs. stimulation frequency data from single fibres repeated after 60 min of constant perfusion at an extracellular of 40 Torr and 5 Torr, and 5 Torr in the presence of SS31 (40 Torr, filled circles; 5 Torr, open circles; and at 5 Torr plus SS31, filled triangles; n = 7). C, changes in tension generation during a fatiguing stimulation protocol at an extracellular of 5 Torr for control and SS31 treated fibres (control, filled circles; SS31, filled triangles; n = 7 fibres per group).