Figure 9.

The effect of reducing cardiac workload via Langendorff heart perfusions on metabolic fluxes relevant to energy production and the citric acid cycle. A, glycolytic efflux of lactate and pyruvate formed from exogenous [U-¹³C₆]glucose. B, percentage contribution of exogenous [U-¹³C₆]glucose to the intracellular pyruvate pool. C, percentage contribution to acetyl-CoA formation of exogenous [U-¹³C₆]glucose via pyruvate decarboxylation (PDC_glu) relative to citrate synthesis (CS). D, percentage contribution of exogenous [U-¹³C₆]glucose to anaplerosis via pyruvate carboxylation (PC_glu) relative to CS. E, ratio of exogenous [U-¹³C₆]glucose undergoing PC_glu to PDC_glu. Horizontal bars, means ± S.E. (error bars). For the Beating group, n = 7 in A and n = 6 for all other graphs. For the Nonbeating group, n = 8 for all graphs. *, p < 0.05 Beating versus Nonbeating.