1. Decreased activity of uroporphyrinogen decarboxylase caused by 2,4,5,3′,4′-pentabromobiphenyl in chick embryo hepatocyte cultures
- Author
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Jacqueline F. Sinclair, Peter R. Sinclair, Herbert L. Bonkowsky, William J. Bement, George H. Elder, and S.G. Smith
- Subjects
Porphyrins ,Carboxy-Lyases ,Uroporphyrinogen III decarboxylase ,Polybrominated Biphenyls ,Cell ,Biophysics ,Chick Embryo ,Biology ,Biochemistry ,Structural Biology ,In vivo ,Polybromobiphenyl ,Genetics ,medicine ,Animals ,Uroporphyrinogen Decarboxylase ,Uroporphyrinogen decarboxylase activity ,Molecular Biology ,Incubation ,Cells, Cultured ,chemistry.chemical_classification ,Porphyria ,Biphenyl Compounds ,Uroporphyrin ,Embryo ,Aminolevulinic Acid ,Cell Biology ,Molecular biology ,medicine.anatomical_structure ,Enzyme ,Liver ,chemistry ,Hepatocyte - Abstract
Uroporphyrinogen decarboxylase activity was investigated in cultures of chick embryo liver by two different methods: (1) analysis of porphyrin composition following incubation of intact cells with δ-aminolevulinic acid; and (2) a more conventional direct enzymic assay of cell homogenates. Activity was detectibly decreased following exposure of cells to 100 ng/ml 2,4,5,3′,4′-pentabromobiphenyl using the first method, but not the second. This decrease in activity was reversed by homogenizing the cells treated with 100 ng/ml pentabromobiphenyl. It is concluded that the direct homogenate assay of the enzyme may miss or underestimate decreases in its in vivo activity.
- Published
- 1983
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