QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online March 22, 2004
Journal of Experimental Biology 207, 1533-1542 (2004)
Published by The Company of Biologists 2004
doi: 10.1242/jeb.00919

This Article Summary Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Chung-Davidson, Y.-W. Articles by Li, W. Search for Related Content PubMed PubMed Citation Articles by Chung-Davidson, Y.-W. Articles by Li, W.

ß-naphthoflavone induction of CYP1A in brain of juvenile lake trout (Salvelinus namaycush Walbaum)

Yu-Wen Chung-Davidson, Christopher B. Rees, Hong Wu, Sang-Seon Yun and Weiming Li^*

Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI 48824, USA

View larger version (13K): [in a new window]   Fig. 1. Time course for ß-naphthoflavone (BNF)-induced CYP1A mRNA measured by Q-RT-PCR. Juvenile lake trout were randomly assigned to treatment groups (N=8 for each treatment group) and given an intraperitoneal injection of BNF in corn oil (50 mg kg–1 body mass) or corn oil alone. Whole brain tissue was taken at 10 different time periods between time zero and 32 days. Total RNA was extracted and analyzed for CYP1A mRNA levels using Q-RT-PCR. Data were analyzed using a two-way analysis of variance followed by a Tukey–Kramer adjustment for all pairwise comparisons. At most time periods, significantly higher levels of CYP1A expression were found in each induced group over its respective control group (designated by *; Tukey–Kramer, P<0.0001).

View larger version (94K): [in a new window]   Fig. 2. (A) In situ hybridization expression patterns of CYP1A mRNA in juvenile lake trout midbrain of control fish and fish exposed to ß-naphthoflavone (BNF) for 4 days. CYP1A mRNA-positive cells are denoted by blue stain. Control fish were injected with corn oil vehicle daily for 4 days before sacrifice. Scale bars, 100 µm. (B) Higher magnification of BNF-exposed fish midbrain showing blue-stained glial cells (black arrows) and endothelia (gray arrow). Scale bar, 10 µm. Horizontal sections were counterstained with nuclear Fast Red.

View larger version (75K): [in a new window]   Fig. 3. CYP1A-immunoreactive (black) glial cells in the corpus cerebelli and the tectum mesencephali of the control juvenile lake trout. Note that the glial cell courses along the blood vessels, and the end feet (black arrow) and dendritic spines (grey arrow) are visible. Horizontal section (20 µm thick) is counterstained with hematoxylin nuclear stain (purple). Scale bars, 20 µm.

View larger version (109K): [in a new window]   Fig. 4. CYP1A immunoreactivity (brown/black) in the olfactory bulbs and valvula cerebelli of the control and ß-naphthoflavone (BNF)-treated juvenile lake trout. The black arrow points to an area with CYP1A-immunoreactive cells in the valvula cerebelli of BNF-treated fish. Horizontal sections (20 µm thick) are counterstained with hematoxylin nuclear stain (purple). Scale bars, 100 µm.

View larger version (154K): [in a new window]   Fig. 5. CYP1A immunoreactivity (brown/black) in the torus longitudinalis, corpus cerebelli and tectum mesencephali in the control and ß-naphthoflavone (BNF)-treated juvenile lake trout. Horizontal sections (20 µm thick) are counterstained with hematoxylin nuclear stain (purple). Scale bar, 100 µm.

View larger version (96K): [in a new window]   Fig. 6. (A) CYP1A immunoreactivity (brown/black) in the tectum mesencephali of the control and ß-naphthoflavone (BNF)-treated lake trout. Hemorrhage depressed the immunoreactivity of CYP1A in BNF-treated juvenile lake trout. (B) Multifocal hemorrhage (brown) in the midbrain of the BNF-treated juvenile lake trout. Note that some blood cells have infiltrated into tissues. Black arrows indicate multinucleated white blood cells. Horizontal sections (20 µm thick) are counterstained with hematoxylin nuclear stain (purple). Scale bars, 100 µm.