title: Limited in vivo bioassays on some benzodiazepines: lack of experimental initiating or promoting effect of the benzodiazepine tranquillizers diazepam, clorazepate, oxazepam and lorazepam.
abstract: Four benzodiazepine tranquillizers were tested for their ability to initiate or promote the development of preneoplastic and neoplastic rat liver lesions. In comparison with the liver carcinogen, N-2-fluorenylacetamide, the benzodiazepines exhibited no initiating activity during a 14-week period of daily administration by gavage. To study the promoting activity, N-2-fluorenylacetamide was used to initiate altered foci and neoplastic nodules in rat liver during 8 weeks and then the benzodiazepines were administered by daily gavage for a period of 12 weeks. The liver tumor promoter phenobarbital had a substantial enhancing effect upon the persistence of nodules but none of the benzodiazepines showed a similar effect. Thus, in the process model systems used, to detect initiating or promoting potential effect, the benzodiazepine tranquillizers failed to exhibit either an initiating or a promoting action.
mesh_terms: D015073:2-Acetylaminofluorene / Q000633:toxicity; D000818:Animals; D014151:Anti-Anxiety Agents / Q000633:toxicity*; D001681:Biological Assay; D002273:Carcinogens; D003009:Clorazepate Dipotassium / Q000633:toxicity; D003975:Diazepam / Q000633:toxicity; D008140:Lorazepam / Q000633:toxicity; D008297:Male; D010076:Oxazepam / Q000633:toxicity; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors
chemical_list: D014151:Anti-Anxiety Agents; D002273:Carcinogens; D003009:Clorazepate Dipotassium; D010076:Oxazepam; D015073:2-Acetylaminofluorene; D008140:Lorazepam; D003975:Diazepam