A Non-Neuronal Cardiac Cholinergic System Plays a Protective Role in Myocardium Salvage during Ischemic Insults
Figure 3
ChAT KO HL-1 cells are susceptible to norepinephrine (NE)-induced cell death.
Cell viability of ChAT KO cardiac cells, as assessed by comparisons with control cells, was dose-dependently decreased by NE treatment, but control cells treated with 2 mM NE appeared to remain intact appearance (vs. control: 29.4±2.4%; P<0.01, n = 8). After treatment with 2 mM NE, ChAT KO cells produced more reactive oxygen species, as indicated by increased APF red fluorescence compared with control cells. Scale bar: 10 µm. ChAT KO cells increased active caspase-3 expression at basal condition (vs. control at 0 h: P<0.01, n = 6), and after NE treatment caspase-3 activation was further enhanced in ChAT KO cells (vs. control at 24 h: 2071±20.8%: P<0.01, n = 6), indicating that the system plays a role in protecting cardiomyocytes from NE toxicity.