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The role of 5-aminolaevulinate synthase, haem oxygenase and ligand formation in the mechanism of maintenance of cytochrome P-450 concentration in hepatocyte culture.

ABSTRACT: The present work shows that the ability of pyridines e.g. metyrapone, to maintain the cytochrome P-450 concentration in cultured hepatocytes is not due to their ability to alter the 5-aminolaevulinate synthase and haem oxygenase activities of the hepatocytes. Since ligands such as metyrapone will prevent the cobalt-mediated loss of hepatic cytochrome P-450 in rats, the hypothesis that ligand formation is the mechanism of maintenance of the cytochrome in hepatocyte culture was tested. The observation that non-pyridine ligands will maintain the cytochrome P-450 concentration supports this hypothesis.

SUBMITTER: Hockin LJ

PROVIDER: S-EPMC1154299 | biostudies-other | 1983 Mar

REPOSITORIES: biostudies-other

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Maintenance of total cytochrome P-450 content in rat hepatocyte culture and the abundance of CYP1A2 and CYP2B1/2 mRNAs.

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The relationship between delta-aminolaevulinate synthetase induction and the concentration of cytochrome P-450 and catalase in rat liver.

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