Figure 3. Effects of 10 μM Ba2+ on reentry frequency and stability in TG hearts.
A, representative experiment. Left, onset of reentry. Dominant frequency (DF) is ∼46 Hz. Middle, 1 min after onset of reentry; DF is stable at ∼48 Hz. Right, 1.5 min after onset of 10 μm Ba2+ perfusion; DF slowed down to 24 Hz. Reentry stopped immediately thereafter. B, composite data from five TG heart experiments. Frequency of activation is normalized to the maximal frequency in the DF map. Perfusion with 10 μm Ba2+ reduced reentry frequency by ∼50% of control before termination.