Superfund Research Program
Effects of Arsenic on Cytochrome P450
Project Leader: Jacqueline F. Sinclair (Dartmouth Medical School)
Grant Number: P42ES007373
Funding Period: 1995 - 2005
During the past year, it has been found that treatment with non-toxic doses of arsenic caused concentration-dependent decreases in barbiturate-mediated induction of cytochrome P450 2H in cultured chick embryo hepatocytes and cytochrome P450 2B in cultured rat hepatocytes. Induction of 5-aminolevulinic acid decreased in parallel with the decrease in cytochrome P450 2H. Both cultured chick embryo and rat hepatocytes accumulated zinc protoporphyrin from the precursor, aminolevulinic acid, but differed in responses to exogenous lead and zinc. This research is increasing the understanding of whether certain forms of cytochrome P450 are more susceptible to the effects of heavy metals than others.