Figure 1. Characterization of Ca²⁺ retention of Crangon crangon (A, C) and Palaemon serratus (B, D) mitochondria. A, B.

: Time courses of CaGr-5N fluorescence (arbitrary units, black traces) reflecting extramitochondrial [Ca²⁺], in parallel to light scattering at 660/660 nm (arbitrary units, grey traces), reflecting mitochondrial swelling. 200 µM CaCl₂ was added where indicated by the arrowheads. 40 µg of alamethicin (Alm) was added where indicated. Results shown in panels A and B are representative of at least 4 independent experiments. C, D: Bar graphs of maximum Ca²⁺ uptake capacity (% scale) calculated from the number of 100 µM CaCl₂ additions given to mitochondria until no further decrease in CaGr-5N fluorescence (implying maximum mitochondrial calcium uptake) was observed, in the presence of 1 µM cyclosporin A or 20 µM BKA, (n = 3). The rates of Ca²⁺ uptake of the last addition were compared among treatment groups, where it exhibited a small variability, but no statistical significance (p = 0.933 for Crangon crangon and p = 0.989 for Palaemon serratus, ANOVA on Ranks). The rates of Ca²⁺ uptake of all previous CaCl₂ additions were virtually identical among all treatment groups.