Event Abstract Back to Event Effects of Salinity Challenge on Ion Regulation in Early and Late Upstream Migrating Sea Lamprey, Petromyzon marinus. Diogo Ferreira-Martins1, 2*, Stephen D. McCormick3, João Coimbra1, 2 and Jonathan M. Wilson1, 4* 1 Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Portugal 2 Instituto de Ciências Biomédicas Abel Salazar, University of Porto, Portugal 3 Conte Anadromous Fish Research Center, USGS, United States 4 Wilfrid Laurier University, Canada The sea lamprey, Petromyzon marinus, is an anadromous species in which the adults re-enter freshwater, and migrate upstream for terminal spawning. A reduction in salinity tolerance has been document in migrants although the underlying mechanisms have not been characterized. The aim of this study was to determine the capacity for marine osmoregulation in late, upstream migrants by characterizing the morphological and physiological effects of salinity challenge from a molecular perspective. For this two experiments were performed using early and late upstream migrants. Animals salinity limited was found to be 17.5‰ for late upstream migrants, thought some early migrants were able to perform at 24‰. A number of relevant blood and intestinal parameters were measured to assess ionoregulatory and biochemical changes as well as the expression of key ion-transport related proteins by immunoblotting (IB) [Na+/K+-ATPase (NKA), vacuolar-type H+-ATPase, carbonic anhydrase, and Na+:K+:2Cl-contransporter]. NKA activity was also measured, in addition to oxidative stress indicators. The Na+ and Cl- levels with plasma and intestinal fluid were quantified and it was found that in non performing animals these fluids approached environmental concentrations (osmoconforming and failure of drinking mechanism, respectively). A drop in hematocrit was also observed with plasma lactate indicating hemolytic anemia. Plasma [ALT], GST activity and [GSH] were used to assess oxidative damage to tissues. An increase in Na+/K+-ATPase activity in mid-intestine in late migrants and posterior intestine in early migrates showed a potentially adaptive ionoregulatory response to salinity increase. (FCT grant PTDC/MAR/98035/2008). Keywords: Seawater acclimation, Spawning Migration, Ionoregulation, osmoregulation, osmotic stress Conference: XV European Congress of Ichthyology, Porto, Portugal, 7 Sep - 11 Sep, 2015. Presentation Type: Oral Presentation Topic: Physiology, Behavior and Toxicology Citation: Ferreira-Martins D, McCormick SD, Coimbra J and Wilson JM (2015). Effects of Salinity Challenge on Ion Regulation in Early and Late Upstream Migrating Sea Lamprey, Petromyzon marinus.. Front. Mar. Sci. Conference Abstract: XV European Congress of Ichthyology. doi: 10.3389/conf.fmars.2015.03.00018 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 23 Oct 2015; Published Online: 04 Nov 2015. * Correspondence: Dr. Diogo Ferreira-Martins, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Porto, 4050-123, Portugal, diogofmartins14@gmail.com Prof. Jonathan M Wilson, Interdisciplinary Centre of Marine and Environmental Research (CIIMAR), University of Porto, Porto, 4050-123, Portugal, wilson.jm.cimar@gmail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Diogo Ferreira-Martins Stephen D McCormick João Coimbra Jonathan M Wilson Google Diogo Ferreira-Martins Stephen D McCormick João Coimbra Jonathan M Wilson Google Scholar Diogo Ferreira-Martins Stephen D McCormick João Coimbra Jonathan M Wilson PubMed Diogo Ferreira-Martins Stephen D McCormick João Coimbra Jonathan M Wilson Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.