Fig. 1. Time course of changes in maximal rates of pyruvate oxidation by mitochondria from oxidative muscle during warm and cold acclimation. Rates are expressed per mg mitochondrial protein, per nmol ADP-ATP translocase (ANT), per nmol cytochrome b (cyt. b) and per mg phospholipids. Data are means ± S.E.M. When rates at a given assay temperature during each acclimation experiment differ, they are followed by different letters (P0.05; ANOVA and Tukey's a posteriori test). *Denotes a significant difference between final cold rate (week 10) and initial cold rate (initial in warm acclimation). No differences were found between final warm rate (week 8) and initial warm rate (initial in cold acclimation). The number of individuals for each experiment is shown in Table 1. NA, not available.