Figure 3: Hepatocyte respiration. Liver specimens were incubated at 37°C in 50 mL KH buffer (continuously gassed with 95% O2: 5% CO2) with and without designated concentrations of sorafenib or regorafenib. At specific time periods, samples were washed with KH buffer and processed for O2 measurements at 37°C. Representative runs are shown. The lines are linear fits. The rate of respiration (k , μM O2 min-1) was set as the negative of the slope of [O2] vs.t. The values of k c (μM O2 min-1 mg-1) are shown at the bottom of each run. Panel A: Liver cellular respiration with and without 2.5 μM sorafenib. Panel B: Liver cellular respiration with and without 5 μM regorafenib. Panel C: Liver cellular respiration with and without 50 μM sorafenib or 50 μM regorafenib.