Mardones, J.I.Shabala, L.Shabala, S.Dorantes-Aranda, J.J.Seger, A.Hallegraeff, G.M.2023-07-102023-07-102018Harmful Algae, 2018; 80:55-631568-98831878-1470https://hdl.handle.net/2440/138882Available online 28 September 2018Harmful algal blooms (HAB) are responsible for massive mortalities of wild and aquacultured fish due to noticeable gill damage, but the precise fish-killing mechanisms remain poorly understood. A non-invasive microelectrode ion flux estimation (MIFE) technique was successfully applied to assess changes in membrane-transport processes in a model fish gill cell line exposed to harmful microplankton. Net Ca2+, H+, K+ ion fluxes in the rainbow trout cell line RTgill-W1 were monitored before and after addition of lysed cells of this Paralytic Shellfish Toxins (PST) producer along with purified endocellular dinoflagellate PST. It was demonstrated that PST alone do not play a role in fish gill damage during A. catenella outbreaks as previously thought, but that other ichthyotoxic metabolites from lysed algal cells (i.e. lipid peroxidation products or other unknown metabolites) result in net K+ efflux from fish gill cells and thereby gill cell death.en© 2018 Elsevier B.V. All rights reserved.Fish-killing; Alexandrium catenella; Ichthyotoxins; PST; RTgill-W1; Cell membrane ion fluxesCell LineGillsAnimalsOncorhynchus mykissMarine ToxinsMicroelectrodesIon TransportHarmful Algal BloomMicroalgaeJournal article10.1016/j.hal.2018.09.0042023-07-06531807Seger, A. [0000-0001-7018-0455]