US EPA

2184005 

Journal Article 

Cytochromes P-4501A activity and mRNA level in liver and lungs of rats induced with various xenobiotics 

Sharipova, GA; Gulyaeva, LF; Lyakhovich, VV 

1998 

1 

Molecular Biology
ISSN: 0026-8933
EISSN: 1608-3245 

PLENUM PUBL CORP 

NEW YORK 

32 

3 

471-474 

English 

WOS:000074724500024 

A comparative analysis was done on the levels of mRNA for cytochromes P-4501A1 and 1A2 and the corresponding activities of 7-ethoxyresorufin- and 7-methoxyresorufin-O-dealkylases in liver and lungs of rats upon induction with 3-methylcholanthrene, benzo[a]pyrene, beta-naphthoflavone, Arochlor 1254, and hexachlorobenzene. The increase in the CYP1A1 mRNA level in liver and lungs was accompanied with a rise in the 7-ethoxyresorufin-O-dealkylase activity, to imply transcriptional mechanisms of CYP1A1 induction. Both in liver and in lungs of the animals induced, no correlation between the 7-methoxyresorufin-O-demethylase activity of CYP1A2 and its mRNA content was revealed, which indicates the existence of posttranscriptional mechanisms of regulation of the CYP1A2 gene expression. Moreover, the activity of this enzyme depended on the type of the inducer. Comparison of the data on the mRNA level and the enzymic activities showed that induction of CYP1A1 and CYP1A2 is regulated by different molecular mechanisms. 

cytochrome P-4501A; induction; 3-methylcholanthrene; Arochlor 1254; hexachlorobenzene; benzo[a]pyrene; beta-naphthoflavone; gene expression; liver; lungs