Fig. 3.

Kinetics of the initial fast-phase rate of [Ca²⁺]_c decay (λ₁) at different time points of a repetitive contractile bout in the presence and absence of BTS. A and B: trace recordings of [Ca²⁺]_c decay after stimulation period (starting at 0 s) at different time points during the contractile bouts in the absence (control; A) and the presence of BTS (BTS; B). In A, the first contraction is shown (a), then the 62nd contraction (360 s; b), and the fatigue time point (c). In B, the first contraction is shown (a), then the 62nd contraction (360 s; b), and the last contraction (d). C: fast-phase rate of [Ca²⁺]_c decay (λ₁) in the absence (●) and the presence of BTS (○). n = 5 fibers. *P < 0.05 vs. initial contraction, one-way ANOVA, repeated measures; **P < 0.05 control vs. BTS, two-way repeated-measures ANOVA. Values are expressed as means ± SE. The time points shown in A and B are indicated in C as a, b, c, and d.