Physiological effects of waterborne lead exposure in spiny dogfish (Squalus acanthias).

Autor: Eyckmans M; Laboratory for Ecophysiology, Biochemistry and Toxicology, University of Antwerp, Belgium. marleen.eyckmans@ua.ac.be, Lardon I, Wood CM, De Boeck G
Jazyk: angličtina
Zdroj: Aquatic toxicology (Amsterdam, Netherlands) [Aquat Toxicol] 2013 Jan 15; Vol. 126, pp. 373-81. Date of Electronic Publication: 2012 Sep 20.
DOI: 10.1016/j.aquatox.2012.09.004
Abstrakt: To broaden our knowledge about the toxicity of metals in marine elasmobranchs, cannulated spiny dogfish (Squalus acanthias) were exposed to 20 μM and 100 μM lead (Pb). Since we wanted to focus on sub lethal ion-osmoregulatory and respiratory disturbances, arterial blood samples were analysed for pH(a), PaO(2), haematocrit and total CO(2) values at several time points. Plasma was used to determine urea, TMAO, lactate and ion concentrations. After 96 h, Pb concentrations were determined in a number of tissues, such as gill, rectal gland, skin and liver. To further investigate ion and osmoregulation, Na(+)/K(+)-ATPase activities in gill and rectal gland were analysed as well as rates of ammonia and urea excretion. Additionally, we studied the energy reserves in muscle and liver. Pb strongly accumulated in gills and especially in skin. Lower accumulation rates occurred in gut, kidney and rectal gland. A clear disturbance in acid-base status was observed after one day of exposure indicating a transient period of hyperventilation. The increase in pH(a) was temporary at 20 μM, but persisted at 100 μM. After 2 days, plasma Na and Cl concentrations were reduced compared to controls at 100 μM Pb and urea excretion rates were elevated. Pb caused impaired Na(+)/K(+)-ATPase activity in gills, but not in rectal gland. We conclude that spiny dogfish experienced relatively low ion-osmoregulatory and respiratory distress when exposed to lead, particularly when compared to effects of other metals such as silver. These elasmobranchs appear to be able to minimize the disturbance and maintain physiological homeostasis during an acute Pb exposure.
(Copyright © 2012 Elsevier B.V. All rights reserved.)
Databáze: MEDLINE