DEVELOPMENT OF A V79 CELL-LINE EXPRESSING HUMAN CYTOCHROME-P450 2D6 AND ITS APPLICATION AS A METABOLIC SCREENING TOOL

Expression of human cytochrome P450 (CYP) in heterologous cells is a m eans of specifically studying the role of these enzymes in drug metabo lism. The complete cDNA encoding CYP2D6-VAL(374) was inserted into an expression vector containing the strong myeloproliferative sarcoma vir us promotor in combination with the enhancer of the cytomegalovirus an d stably expressed in V79 Chinese hamster cells. The presence of genom ically integrated CYP2D6 cDNA was confirmed by polymerase chain reacti on analysis. The protein expression was shown by Western blotting. Fun ctional expression could be demonstrated by O-demethylation of dextrom ethorphan to dextrorphan in live cells. The enzymatic activity of 154 +/- 16 pmol min(-1) mg(-1) protein was comparable with dextromethorpha n-O-demethylation activities of human liver. The metabolism of two dop aminergic ergoline derivatives was investigated in whole recombinant V 79 cells. Both lisuride and terguride were monodeethylated; in case of lisuride a correlation to the in vivo situation was demonstrated comp aring poor and extensive metabolizers. (C) 1997 Elsevier Science B.V.