|Document Type:||Journal Article|
|Title:||Crude oil impairs cardiac excitation-contraction coupling in fish|
|Author:||F. Brette, B. Machado, C. Cros, J. P. Incardona, N. L. Scholz, B. A. Block|
|Keywords:||oil spill,embryo,fish health,toxicity,PAHs,pollution|
Crude oil is known to disrupt cardiac function in fish embryos. Large oil spills, such as the Deepwatter Horizon (DWH) disaster that occurred in 2010 in the Gulf of Mexico, could severely affect fish at impacted spawning sites. The physiological mechanisms underlying such potential cardiotoxic effects remain unclear. Here, we show that crude oil samples collected from the DWH spill prolonged the action potential of isolated cardiomyocytes from juvenile bluefin and yellowfin tunas, through the blocking of the delayed rectifier potassium current (Ikr). Crude oil exposure also decreased calcium current (ICa) and calcium cycling, which disrupted excitation-contraction coupling in cardiomyocytes. Our findings demonstrate a cardiotoxic mechanism by which crude oil afftects the regulation of cellular excitability, with implications for life-threatening arrhythmias in vertebrates.