Figure 9.

Mitochondrial sequestration of Ca²⁺ released from caffeine-sensitive stores. Cells were coloaded with rhod-2 and Calcium Green and examined in perforated patch as in Fig. 4. (A) Ca_m and Ca_c responses from another cell subjected to sequential depolarizations of 0.5 s applied before (circle), and of 1.0 or 1.5 s (box) applied after perfusion with 10 mM caffeine and 10 μM BHQ. (B) Averaged responses from three cells treated exactly as above. The enlarged, closed symbols mark the observed Ca_m and Ca_c values at the termination of stimulus. The intermediate response to the first depolarization applied after treatment is not shown, to avoid excessive overlap of records.