Fig. 2
Comparison of membrane currents and I–V relationships of isolated PV cardiomyocytes from rat, guinea pig, and rabbit. A Current traces were obtained from PV cardiomyocytes of rat (a), guinea pig (b), and rabbit (c) in a normal Tyrode’s solution. Traces shown were obtained by applying 500-ms depolarizing or hyperpolarizing pulses from a holding potential of − 40 mV to a test potential from − 100 mV to + 60 mV. In PV cardiomyocytes of rabbit, two obviously different families of currents were detected, where some cells possessed transient outward current (left) and others did not (right). Dashed lines indicate the zero current level. BI–V relationships for the initial current (open circles) and the current near the end of the pulses (filled circles) in rat (a), guinea pig (b), and rabbit (c). A transient outward current was shown only in rabbit (open squares)