US EPA

597447 

Journal Article 

Abstract 

Dietary Aroclor 1254-induced changes in global gene expression in Fisher rats 

Basford, T; Means, J 

2004 

1 

Toxicologist
ISSN: 0731-9193 

TOX/4001461 

78 

1-S 

246 

English 

Dietary intake is a primary route for biomagnification of environmentally persistent polyclorinated biphenyls (PCBs) within humans and animals, as these hydrophobic compounds partition to and accumulate in lipid tissues. Exposure to PCBs in vivois associated with varied toxic responses such as alterations in blood and lipid biochemistry, immune suppression, neoplastic lesions, and impaired nerological function (Safe, 1993; Waring, et.al., 2001). To date, no microarray studies of the impact of PCB ingestion on global gene expression, at either acute or chronic levels, have been reported. Changes in expression of 8800 hepatic genes in Fisher 344 male rats were assessed by Affymetrix microarray analysis to identify important physiological pathways affected by dietary PCBs. Six week old animals were fed control food or food containing 10 ppm or 50 ppm Aroclor 1254 for 7 days (acute) and 84 days (chronic). Two arrays were prepared from liver mRNA for each dose and timepoint; a threefold or greater change in signal between control and treated genes was considered significant. Blood serum levels of lipids (cholesterol, triglycerides), bilirubin, and enzyme markers of liver health (ALT, AST, ALP, GGT) were also measured and correlated to changes in gene expression. Safe S., Toxicology, structure-function relationship, and human and environmental health impacts of polychlorinated biphenyls: progress and problems. 

Society of Toxicology Annual Meeting