Fig. 4.

Phenanthrene (Phe) disrupts cardiac ion flux in isolated brown trout ventricular cardiomyocytes. (A) Effect of Phe on action potential duration (APD). (Ai) Representative traces of action potential elicited at 0.5 Hz in absence (Control) and presence of 10 μM Phe and (Aii) Mean action potential duration at 10% (APD₁₀), 50% (APD₅₀) and 90% (APD₉₀) in absence (Control) and presence of 10 μM and 30 μM Phe (n = 5 for each data set from min. two fish). (B) Effect of Phe on I_kr currents. (Bi) Representative traces of I_kr currents in absence (Control) and presence of 10 μM Phe; inset – voltage protocol used to elicit I_kr currents. (Bii) Bar graph of mean I_kr current density in absence (Control) and presence of 10 μM Phe (*** p=0.0002; n = 6 from min. two fish). (Biii) concentration-response curve yielded an the IC₅₀ value of 7.2 ± 0.6 μM (n = 6 for each data set from min. two fish). (C) Effect of Phe on I_CaL currents. (Ci) Representative trace of I_CaL currents in absence (Control) and presence of 30 μM Phe; inset – voltage protocol used to elicit I_CaL currents. (Cii) Mean I_CaL current density in absence (Control) and presence of 30 μM Phe (** p=0.001; n = 4 from two fish). Values are mean ± S.E.M (total n = 34 from total of 8 fishes).