TY - JOUR
T1 - Plasma clearance of cadmium and zinc in non-acclimated and metal-acclimated trout
AU - Chowdhury, M. Jasim
AU - Grosell, M.
AU - McDonald, D. G.
AU - Wood, C. M.
N1 - Funding Information:
We are grateful to Dr Peter Chapman for helpful comments on the manuscript. This study was financially supported by a Strategic Research Grant from the Natural Sciences and Engineering Research Council (NSERC) of Canada and by the International Copper Association (ICA), the International Lead Zinc Research Organization (ILZRO), The Nickel Producers Environmental Research Association (NiPERA), Falconbridge, Cominco, and Noranda. C.M. Wood is supported by the Canada Research Chair Program.
PY - 2003/8/20
Y1 - 2003/8/20
N2 - Adult rainbow trout were pre-exposed to a sublethal concentration of waterborne cadmium (Cd, 26.7 nmol/l) or waterborne zinc (Zn, 2294 nmol/l) for 30 days to induce acclimation. A single dose of radiolabeled Cd (64.4 nmol/kg) or Zn (183.8 nmol/kg) was injected into the vascular system of non-acclimated and Cd- or Zn-acclimated trout through indwelling arterial catheters. Subsequently, repetitive blood samples over 10 h and terminal tissue samples (liver, heart, bile, stomach, intestine, kidney, gills, muscle, and spleen) were taken to characterize the effect of metal acclimation on clearance kinetics in vivo. Plasma clearance of Cd in Cd-acclimated fish (0.726±0.015 and 0.477±0.012 ml/min per kg for total and newly accumulated Cd, respectively), was faster than that in non-acclimated trout (0.493±0.013 and 0.394±0.009 ml/min per kg). Unlike plasma Cd, the levels of Cd in red blood cells (RBCs) were 1.2-2.2 times higher in Cd-acclimated fish than in non-acclimated fish. At 10 h post-injection, the liver accumulated the highest proportion (∼22%) of the injected Cd dose in both non-acclimated and Cd-acclimated fish but did not account for the difference in plasma levels of Cd between two groups. Plasma clearance of Zn (∼0.23 ml/min per kg for new Zn) was substantially lower than Cd clearance. Pre-acclimation to waterborne Zn reduced the new Zn levels in RBCs, but did not affect the clearance of Zn from blood plasma or tissue burdens of Zn in fish. Bile concentrations of both Cd and Zn were elevated in acclimated fish, but total bile burden accounted for <1% of the injected metal dose. The results suggest that the detoxification process of injected plasma Cd is stimulated by pre-acclimation to waterborne Cd, and that Zn levels are homeostatically controlled in both non-acclimated and acclimated trout.
AB - Adult rainbow trout were pre-exposed to a sublethal concentration of waterborne cadmium (Cd, 26.7 nmol/l) or waterborne zinc (Zn, 2294 nmol/l) for 30 days to induce acclimation. A single dose of radiolabeled Cd (64.4 nmol/kg) or Zn (183.8 nmol/kg) was injected into the vascular system of non-acclimated and Cd- or Zn-acclimated trout through indwelling arterial catheters. Subsequently, repetitive blood samples over 10 h and terminal tissue samples (liver, heart, bile, stomach, intestine, kidney, gills, muscle, and spleen) were taken to characterize the effect of metal acclimation on clearance kinetics in vivo. Plasma clearance of Cd in Cd-acclimated fish (0.726±0.015 and 0.477±0.012 ml/min per kg for total and newly accumulated Cd, respectively), was faster than that in non-acclimated trout (0.493±0.013 and 0.394±0.009 ml/min per kg). Unlike plasma Cd, the levels of Cd in red blood cells (RBCs) were 1.2-2.2 times higher in Cd-acclimated fish than in non-acclimated fish. At 10 h post-injection, the liver accumulated the highest proportion (∼22%) of the injected Cd dose in both non-acclimated and Cd-acclimated fish but did not account for the difference in plasma levels of Cd between two groups. Plasma clearance of Zn (∼0.23 ml/min per kg for new Zn) was substantially lower than Cd clearance. Pre-acclimation to waterborne Zn reduced the new Zn levels in RBCs, but did not affect the clearance of Zn from blood plasma or tissue burdens of Zn in fish. Bile concentrations of both Cd and Zn were elevated in acclimated fish, but total bile burden accounted for <1% of the injected metal dose. The results suggest that the detoxification process of injected plasma Cd is stimulated by pre-acclimation to waterborne Cd, and that Zn levels are homeostatically controlled in both non-acclimated and acclimated trout.
KW - Chronic
KW - Homeostasis
KW - Kinetics
KW - Red blood cells
KW - Waterborne
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U2 - 10.1016/S0166-445X(03)00074-2
DO - 10.1016/S0166-445X(03)00074-2
M3 - Article
C2 - 12842591
AN - SCOPUS:0038384023
VL - 64
SP - 259
EP - 275
JO - Aquatic Toxicology
JF - Aquatic Toxicology
SN - 0166-445X
IS - 3
ER -