Para-aminophenol metabolism in an established cell line with liver-like functions.

The clonal MH1C1-strain of rat hepatoma cells in culture metabolizes p-aminophenol (PAP), measured both by substrate disappearance and by PAP-glucuronide formation. PAP-glucuronide was assayed by spectrophotometric determination of the diazotized product coupled with naphthyl-ethylenediamine. In addition to glucuronidation, some of the drug is metabolized apparently by other pathway(s). Cultured cloned rat fibroblasts also exhibit PAP-glucuronidation activity, whereas they do not conjugate bilirubin. Chang cells do not glucuronidate PAP. Flavaspidic acid has no effect on the PAP-glucuronidation in the liver cells nor in the fibroblasts, in contrast to the inhibitory action seen on bilirubin conjugation by the same liver cells.