In a sheep model of persistent AF, NOS3 transcript levels are attenuated and circulating NOx levels decreased. Persistent AF is associated with increased oxidative stress, probably resulting from increased NADPH oxidase activity, without major changes in anti-oxidant capacity of the atrial tissue.
Lenaerts, I., Driesen, R. B., Blanco, N. H., Holemans, P., Heidbüchel, H., Janssens, S., Balligand, J.-L., Sipido, K. R., & Willems, R. (2013). Role of nitric oxide and oxidative stress in a sheep model of persistent atrial fibrillation. Europace, 15(5), 754-760. https://doi.org/10.1093/europace/eut012 (Original work published 2013)