Graduate Thesis Or Dissertation

 

The effect of chronic exposure of chinook salmon to benzo(a)pyrene and cortisol of CYP1A1 induction and susceptibility to a microsporidian parasite, Loma salmonae Public Deposited

Analytics

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/f7623g98m

Descriptions

Attribute NameValues
Creator
Abstract
  • Wild populations of fish are faced with a multitude of stressors, which may include human interaction, toxins, and disease. Benzo(a)pyrene (BaP), a known carcinogen and immunotoxin, has been reported in the stomach contents of juvenile chinook salmon, Oncorhynchus tshawytscha, in urban waterways. We investigated the impact of chronic dietary exposure of environmentally relevant levels of BaP on the immune system and cytochrome P4501A1 (CYP1A1) expression in juvenile chinook salmon. Two experiments were carried out in which juvenile fish were fed food treated with ethanol (control diet), low or high concentrations of BaP, or cortisol. In the first experiment we measured mitogen-stimulated proliferation of splenic leukocytes using flow cytometry and a colorimetric assay using Alamar Blue[superscript TM] Susceptibility to a microsporidian parasite, Loma salmonae, was evaluated in the second experiment by quantification of xenomas in the gills. Hepatic CYP1A1 and plasma cortisol were measured in both experiments. No significant trends were found in leukocyte mitogen activation or plasma cortisol between treatments or days. However, western blot analysis of CYP1A1 concentration in liver revealed interesting patterns of induction: in cortisol fed groups CYP1A1 was <20% of control on all days, groups fed low levels of BaP were 250% of control values on days 8 and 21 then dropped below control values on day 29, and groups fed high levels of BaP had less CYP1A1 than controls on all days. Similar patterns of CYP1A1 levels were found in the second experiment, and diseased control groups showed about a 55% decrease in CYP1A1 concentration when compared with non-diseased control groups. Susceptibility to L. salmonae was significantly higher in groups receiving cortisol. Whereas there was no effect of the high BaP dose, the low BaP dose appeared to increase disease susceptibility. This study supports concerns of stress and toxin induced immune dysfunction in wild populations of fish.
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
Digitization Specifications
  • File scanned at 300 ppi (Monochrome, 8-bit Grayscale) using ScandAll PRO 1.8.1 on a Fi-6670 in PDF format. CVista PdfCompressor 4.0 was used for pdf compression and textual OCR.
Replaces
Additional Information
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2012-08-09T16:20:57Z (GMT) No. of bitstreams: 1 MarieAmarisa2004.pdf: 3969593 bytes, checksum: f571c9c5a0c9cadd26dfe67a65c749d7 (MD5)
  • description.provenance : Made available in DSpace on 2012-08-09T16:20:57Z (GMT). No. of bitstreams: 1 MarieAmarisa2004.pdf: 3969593 bytes, checksum: f571c9c5a0c9cadd26dfe67a65c749d7 (MD5) Previous issue date: 2003-05-09
  • description.provenance : Submitted by Sergio Trujillo (jstscanner@gmail.com) on 2012-08-08T22:42:41Z No. of bitstreams: 1 MarieAmarisa2004.pdf: 3969593 bytes, checksum: f571c9c5a0c9cadd26dfe67a65c749d7 (MD5)
  • description.provenance : Approved for entry into archive by Patricia Black(patricia.black@oregonstate.edu) on 2012-08-09T16:17:12Z (GMT) No. of bitstreams: 1 MarieAmarisa2004.pdf: 3969593 bytes, checksum: f571c9c5a0c9cadd26dfe67a65c749d7 (MD5)

Relationships

Parents:

This work has no parents.

In Collection:

Items

Thumbnail Title Date Uploaded Visibility Actions
MarieAmarisa2004.pdf 2017-08-19 Public