Fig. 2

BaCl₂ increases [Ca²⁺]_i and muscle force. a Top: representative continuous recording of F₃₄₀/F₃₈₀ illustrates intracellular Ca²⁺ accumulation. Bottom: summary data for F₃₄₀/F₃₈₀ at rest (baseline) and during peak response to 1.2% BaCl₂ in PSS (n = 5) and 1.2% BaCl₂ in Ca²⁺-free PSS (0 [Ca²⁺]_o) (n = 3). b Top: representative continuous recording of force developed by EDL in situ at optimum resting length (L_o) in response to irrigation with 1.2% BaCl₂ for 1 h. Bottom: summary data for resting and peak force in response to 1.2% BaCl₂; values are means ± SEM (n = 4 muscles). ^#P ≤ 0.05 vs. baseline, *P ≤ 0.05 vs. 1.2% BaCl₂ in standard PSS with 2 mM extracellular calcium concentration ([Ca²⁺]_o)