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Impaired Adrenocortical Response to Stress by Brown Trout,Salmo trutta,Living in Metal-Contaminated Waters of the Eagle River, Colorado

https://doi.org/10.1006/gcen.1998.7177Get rights and content

Abstract

Brown trout,Salmo trutta,were collected from two sites contaminated with cadmium (Cd) and zinc (Zn) and one uncontaminated site. These fish were subjected to a continuous confinement stressor in wire cages placed in the river (moderate stress) or in 5-gal. plastic buckets on land (severe stress). Plasma cortisol and corticotropin (ACTH) were determined for fish in buckets by radioimmunoassay after 0, 1, 3, 12, or 24 h of confinement. Plasma cortisol and ACTH levels of brown trout from both contaminated and uncontaminated sites initially were the same and increased with time. However, the rise in plasma cortisol was delayed significantly in fish residing in contaminated sites, even though ACTH secretion initially was elevated compared with control trout. Furthermore, secretion of cortisol and ACTH by these fish declined significantly between 3 and 24 h of confinement. Fish from the uncontaminated site responded more rapidly to confinement with increased cortisol secretion and elevated levels of ACTH and continued to exhibit elevated levels of both hormones up to 24 h of confinement. Caged fish examined after 0, 3, 12, and 24 h of confinement exhibited similar plasma cortisol responses regardless of previous exposure to metals. These results suggest that the overall response to severe, short-term confinement stress by the hypothalamo–pituitary–adrenocortical axis of fish chronically exposed to Cd and Zn was depressed and that these fish could not sustain the stress response as readily as fish living in uncontaminated water.

References (42)

  • A.D. Pickering et al.

    The effects of acute and chronic stress on the levels of reproductive hormones in the plasma of mature male brown trout,Salmo trutta

    Gen. Comp. Endocrinol.

    (1987)
  • T.G. Pottinger et al.

    The corticosteroidogenic response of brown and rainbow trout alevins and fry to environmental stress during a “critical period.”

    Gen. Comp. Endocrinol.

    (1994)
  • T.G. Pottinger et al.

    Testosterone, 11-ketotestosterone, and estradiol-17β modify baseline and stress-induced interrenal and corticotropic activity in trout

    Gen. Comp. Endocrinol.

    (1996)
  • T.G. Pottinger et al.

    The effects of confinement stress on circulating prolactin levels in rainbow trout (Oncorhynchus mykiss

    Gen. Comp. Endocrinol.

    (1992)
  • J.P. Sumpter et al.

    The effects of stress on plasma ACTH, α-MSH, and cortisol levels in salmonids fishes

    Gen. Comp. Endocrinol.

    (1986)
  • D.N. Weber et al.

    Metal redistribution in largemouth bass (Micropterus salmoides

    Comp. Biochem. Physiol. C

    (1992)
  • B.A. Barton

    Stress in finfish: Past, present and future—A historical perspective

    Fish Stress and Health in Aquaculture

    (1997)
  • B.A. Barton et al.

    Effect of electroshock on blood features in juvenile rainbow trout

    J. Fish Biol.

    (1996)
  • D.A. Benoit et al.

    Toxic effects of cadmium on three generations of brook trout (Salvelinus fontinalis

    Trans. Am. Fish. Soc.

    (1976)
  • J.C. Brodeur et al.

    Use of perifusion to assess in vitro the functional integrity of interrenal tissue in teleost fish from polluted sites

    Environ. Toxicol. Chem.

    (1997)
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