title: Verapamil as a co-mutagen in the Salmonella/mammalian microsome mutagenicity test.
abstract: Verapamil is a calcium-channel blocking agent, commonly used for chronic treatment of heart conditions. We have previously demonstrated that verapamil acts as a co-mutagen in a bacterial mutagenicity test for some experimental anilinoacridine antitumour drugs. Within the anilinoacridines series there are several compounds which are apparently non-mutagenic (or very weak mutagens) in the absence of verapamil, but strong mutagens in its presence. We have now tested a wider range of materials for verapamil enhancement of mutagenicity, to include some of those to which persons on verapamil therapy might be exposed through life-style or occupation. Some verapamil enhancement of mutagenicity was seen with most mutagenic compounds including anticancer drugs, antiparasitic agents, one biological stain and one hair dye. A number of tricyclic antidepressants and biological stains were tested and found to be non-mutagenic. If these results extrapolate to mammalian cells, long-term verapamil therapy could potentially increase the effects of certain environmental mutagens.
mesh_terms: D004357:Drug Synergism; D008862:Microsomes, Liver / Q000378:metabolism; D009152:Mutagenicity Tests; D009153:Mutagens / Q000008:administration & dosage*; D012486:Salmonella typhimurium / Q000187:drug effects / Q000235:genetics; D014700:Verapamil / Q000008:administration & dosage* / Q000633:toxicity
chemical_list: D009153:Mutagens; D014700:Verapamil