Evidence of Common Cadmium and Copper Uptake Routes in Zebrafish Danio rerio

• Published in: Environmental science & technology Vol. 48; no. 21; pp. 12946 - 12951
• Main Authors: Komjarova, I, Bury, N.R
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 04.11.2014
• Subjects: Adenosine Triphosphatases - genetics; Adenosine Triphosphatases - metabolism; Agnatha. Pisces; Animal, plant and microbial ecology; Animals; Applied ecology; Aquatic plants; Bioaccumulation; Biological and medical sciences; Cadmium; Cadmium - pharmacokinetics; Cation Transport Proteins - genetics; Cation Transport Proteins - metabolism; Copper; Copper - pharmacokinetics; Copper-transporting ATPases; Danio rerio; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on vertebrates; Fundamental and applied biological sciences. Psychology; Gene Expression Regulation - drug effects; Genes; Gills - drug effects; Gills - physiology; Membrane Transport Proteins - genetics; Membrane Transport Proteins - metabolism; Sodium-Hydrogen Exchangers - genetics; Sodium-Hydrogen Exchangers - metabolism; TRPV Cation Channels - genetics; TRPV Cation Channels - metabolism; Water Pollutants, Chemical - pharmacokinetics; Zebrafish; Zebrafish - genetics; Zebrafish - metabolism; Zebrafish Proteins - genetics; Zebrafish Proteins - metabolism; Cadmium; Detoxification; Transition metal; Metabolism; Uptake; Heavy metal; Toxicokinetics; Trace element; Vertebrata; Brachydanio rerio; Pisces; Poison; Biological accumulation; Copper
• ISSN: 0013-936X; 1520-5851
• DOI: 10.1021/es5032272

Cadmium and copper accumulations in gills of zebrafish were measured during a 48 h exposure to 0.025 μM 106Cd and 0.05 or 0.5 μM 65Cu as a single metal or their mixtures. The gill transcript levels of genes involved in the transport of Cu (CTR1 and ATP7A), Na (NHE-2), Ca (ECaC), divalent metals (DMT1), and Zn (ZIP8) were also compared between treatments at 24 and 48 h. Cd uptake was significantly suppressed in the presence of Cu, indicating interaction between Cu and Cd at uptake sites, but Cu uptake was unaffected by Cd. The decrease in Cd accumulation rates in the presence of Cu was associated with an increase in transcript abundance of ECaC at 24 h and DMT1 at 48 h and a decrease in Zip8 transcript levels, all known as routes for Cd uptake. Fish exposed to 0.5 μM 65Cu show an increase in gill ATP7a transcript abundance, suggesting that Cu is removed from the gill and is transferred to other organs for detoxification. A reduction in gill CTR1 transcript abundance was observed during the Cu–Cd exposure; this may be a regulatory mechanism to reduce Cu loading if Cu is entering the gills by other uptake routes, such as ECaC and DMT1.