Disturbances in hepatic heme metabolism in rats administered alkyl halides

Liver tissue from rats administered 13 different alkyl halides and 4 other hepatotoxins were assayed for indices of hepatic heme synthesis. These included aminolevulinic acid (ALA)-dehydratase activity, porphyrin content, microsomal cytochrome P-450 and reduced glutathione content. Consistent decreases in ALA-dehydratase activity (14 of 17 compounds) and cytochrome P-450 content (14 of 17 compounds) were found. Significant changes in glutathione and porphyrin content also occurred after exposure to some compounds, but were not consistent. Alkyl halides are a class of toxicologically important compounds which have been found to exert an influence on hepatic heme synthesis.