Figure 4

Effects of dobutamine (DOB) and lipopolysaccharide (LPS) on cardiomyocyte Bcl-2 levels, mitochondrial Bax contents, mitochondrial membrane potential and cytochrome c release. Adult mouse ventricular myocytes were treated with DOB (0.02 μM), LPS (10 ng/mL), their combination, or vehicle for 12 hours. (A) Bcl-2 levels were analyzed by western blotting of whole cell lysates. (B) Mitochondrial Bax protein contents were detected by western blotting of mitochondrial proteins and voltage-dependent anion channel (VDAC) was immunoblotted as a mitochondrial marker. (C) Confocal images of JC-1 fluorescence. Mitochondrial membrane potential was visualized in ventricular myocytes stained with JC-1, an indicator of mitochondrial function, green fluorescence indicates monomeric JC-1 (left), red fluorescence represents aggregate JC-1 (middle) and merged channels are shown (right): scale bar = 20 μm. (D) The ratio of monomeric and aggregated JC-1, indicating changes in mitochondrial membrane potential. (E) Cytosolic cytochrome c (Cyt c) contents were analyzed by western blotting of cytosolic proteins and GAPDH was used as an internal control: mean ± standard error of the mean (n = 3). ^* P <0.05 compared with the control group; ^# P <0.05 compared with the LPS group.