Methapyrilene is inactive in the hepatocyte-mediated Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase mutational assay.
Methapyrilene, tested at both non-hepatocytotoxic and hepatocytotoxic concentrations, failed to induce somatic mutations in the hepatocyte-mediated Chinese hamster ovary/hypoxanthine-guanine phosphoribosyl transferase (HGPRT) mutational assay. These data support the conclusion that methapyrilene induces the carcinogenesis process through a non-DNA damaging mechanism, suggested when this antihistamine previously failed to induce a genotoxic response in several in vitro test systems developed to detect carcinogens and mutagens.
D000631:Aminopyridines / Q000633:toxicity*; D000818:Animals; D006224:Cricetinae; D003412:Cricetulus; D005260:Female; D007041:Hypoxanthine Phosphoribosyltransferase / Q000032:analysis; D008113:Liver Neoplasms / Q000139:chemically induced; D008297:Male; D008701:Methapyrilene / Q000633:toxicity*; D009152:Mutagenicity Tests; D009153:Mutagens; D010053:Ovary; D051381:Rats; D011919:Rats, Inbred Strains
D000631:Aminopyridines; D009153:Mutagens; D008701:Methapyrilene; D007041:Hypoxanthine Phosphoribosyltransferase