RT Journal Article SR Electronic T1 Extent and Character of Phenobarbital-Mediated Changes in Gene Expression in the Liver JF Molecular Pharmacology JO Mol Pharmacol FD American Society for Pharmacology and Experimental Therapeutics SP 363 OP 369 VO 51 IS 3 A1 Felix W. Frueh A1 Ulrich M. Zanger A1 Urs A. Meyer YR 1997 UL http://molpharm.aspetjournals.org/content/51/3/363.abstract AB Phenobarbital elicits pleiotropic effects in the liver, including induction of enzymes involved in xenobiotic metabolism. The spectrum of this response was analyzed by differential display of a large population (∼7500) of mRNAs in chicken embryo liver treated in vivo with phenobarbital. We identified 29 cDNA fragments that reproducibly and significantly changed in intensity after a 48-hrin ovo treatment. Eighteen of these (62%) were increased, whereas 11 (38%) were decreased. Twenty strongly regulated cDNA fragments were subcloned and further analyzed. Nucleotide sequence analysis revealed three types of genes: (a) those previously described to be regulated by phenobarbital, including CYP2H1, glutathioneS-transferase, and uridine diphosphate-glucuronosyltransferase; (b) genes reported herein for the first time to be regulated by phenobarbital, including fibrinogen β-chain and γ-chain, retinal glutamine synthetase, apolipoprotein B, two gene products with homologies to elongation factor 1δ and complement factor H, respectively, and (c) several novel genes with hitherto unknown functions. If these data are extrapolated to the entire population of mRNAs of a liver cell, phenobarbital seems to significantly modulate the expression of more than 50 different genes. Our results also demonstrate that a large fraction of genes is negatively regulated by drug treatment. The American Society for Pharmacology and Experimental Therapeutics