Figure 1.

TCA-cycle dependent flux does not increase mitochondrial cAMP. (A) cAMP was measured in isolated liver mitochondria in the presence of 1 mM ATP, and in the absence of inhibitors (white bar), the presence of 30 mM ${\text{HCO}}_3^{-}$ (black bar) or the presence of both ${\text{HCO}}_3^{-}$ and 25 μM KH7 (gray bar). N = 4/condition. * denotes p < 0.05 compared to untreated condition. (B) cAMP was measured in isolated skeletal muscle mitochondria in the presence of 1 mM ATP, and in the absence (black bars) of respiratory substrates or in the presence of pyruvate/malate (white bars), succinate (light gray bars) or palmitoyl-L-carnitine/malate (dark gray bars). For each round of experiments, a single mitochondrial preparation was used for all substrate conditions, including parallel experiments with FCCP, KH7, and acetazolamide (AZA). N = 4 mitochondrial preparations from individual mice.