Oil and gas exploration in the Arctic can result in the release of polycyclic aromatic hydrocarbons (PAHs) into relatively pristine environments. Following the recent spill of approximately 17 500 tonnes of diesel fuel in Norilsk, Russia, May 2020, our study focussed on the effects of phenanthrene, a low molecular weight PAH found in diesel and crude oil, on the isolated atrial and ventricular myocytes from the heart of the polar teleost, the Navaga cod (Eleginus nawaga). Acute exposure to phenanthrene in navaga cardiomyocytes caused significant action potential (AP) prolongation, confirming the proarrhythmic effects of this pollutant. We show AP prolongation was due to potent inhibition of the main repolarising current, I_Kr, with an IC₅₀ value of ~2 µM. We also show a potent inhibitory effect (~55%) of 1 µM phenanthrene on the transient I_Kr currents that protects the heart from early-after-depolarizations and arrhythmias. These data, along with more minor effects on inward sodium (I_Na) (~17% inhibition at 10 µM) and calcium (I_Ca) (~17% inhibition at 30 µM) currents, and no effects on inward rectifier (I_K1 and I_KAch) currents, demonstrate the cardiotoxic effects exerted by phenanthrene on the atrium and ventricle of navaga cod. Moreover, we report the first data that we are aware of on the impact of phenanthrene on atrial myocyte function in any fish species.

在北极进行油气勘探可导致多环芳烃（PAH）释放到相对原始的环境中。继2020年5月在俄罗斯的诺里尔斯克（Norilsk）发生约1.75万吨柴油泄漏之后，我们的研究集中于菲（一种在柴油和原油中发现的低分子量多环芳烃）对分离出的心房和心室肌细胞的影响。极地硬骨鱼类的心脏，纳瓦加鳕鱼（Eleginus nawaga）。Navaga心肌细胞中菲的急性暴露导致明显的动作电位（AP）延长，证实了该污染物的心律失常作用。我们显示AP延长是由于IC ₅₀抑制了主复极化电流I _Kr所致。值为〜2 µM。我们还显示了1 µM菲对瞬态I _Kr电流的有效抑制作用（〜55％），可保护心脏免受早期去极化和心律不齐的影响。这些数据以及对内向钠（I _Na）（在10 µM时约17％的抑制）和钙（I _Ca）（在30 µM时约17％的抑制）电流的较小影响，而对内向整流器（I _K1）的影响_较小。和_IKAch电流，证明了菲对纳瓦加鳕鱼的心房和心室产生的心脏毒性作用。此外，我们报告了第一个数据，我们知道该数据对任何鱼类中菲对心房肌细胞功能的影响。