OBJECTIVESWe have attempted to upgrade and validate an in-house cDNA microarray system developed by our group for the evaluation of chemical toxicity.

METHODSTo establish an in-house microarray, we selected genes that play pivotal roles in detoxifying exogenous substances and maintaining homeostasis in the liver. To validate the system, we examined gene expression profiles in mouse liver following treatment with different doses of carbon tetrachloride (CCl(4)). The data were also analyzed by pathway analysis tools.

RESULTSWe upgraded our array system by collecting genes that are responsive to xenobiotic receptors, apoptosis-related genes, and stress-responsive genes. The acute toxicity of CCl(4) was confirmed by elevated levels of serum transaminase and histopathological findings. The microarray data showed the CCl(4) treatment induced significant changes in gene expression in the mouse liver, and the ingenuity pathways analysis revealed alterations in gene expression in inflammation-related networks.

CONCLUSIONSWe have established a focused microarray system that may be useful for use in toxicogenomics studies. Using this array system, we gained insight into the mechanisms by which CCl(4) exerts its toxic effects. The results of our study also indicate that the combination of focused arrays and bioinformatics tools is helpful in the mechanistic analysis of chemical toxicity.