FIGURE 5.

(A) Panels a–c compare fluorescence images of furaptra (a) and mitotracker green FN (b) and a transmitted light image (c) obtained from an intact myocyte in Ca²⁺-free Tyrode's solution. Times of illumination were 4.2 s (a), 3.1 s (b), and 1.0 s (c). Cell 040204-1. (B) Fluorescence images of furaptra (a) and mitotracker green FN (b) obtained from a skinned myocyte are shown. After saponin treatment (25 μg/ml) for 5 min in the intracellular solution containing 0.8 mM Mg²⁺ and 10 mM Na⁺ (Sol 0.8 Mg/10 Na), the myocyte was incubated in Sol 0.8 Mg/10 Na. The intracellular solution also contained pyruvate (0.1 mM) throughout saponin treatment and fluorescence measurements. Times of illumination were 30.2 s (a) and 6.2 s (b). Cell 061004-10.