title: Comparative study of the carcinogenic activities of nas and some chemical carcinogens when introduced into the buccal pouch of the Syrian hamster.
abstract: Studies were carried out on the carcinogenic effects of nas, 7,12-dimethylbenz-[a]anthracene (DMBA), DMBA+nas, dimethylnitrosamine (DMNA), diethylnitrosamine (DENA), and N-methyl-N-nitrosourea (MNU) when introduced into the buccal pouch of the Syrian hamster. Nas alone induced no tumours in the buccal pouch but tumours at other sites occurred in 18.8% of the treated animals, compared with 4.4% of the controls. Three of 11 hamsters treated with DMBA alone developed tumours. No tumours appeared in the buccal pouch following treatment with DMBA + nas but they developed at other sites in 6 of the 11 hamsters treated. DMNA and DENA induced no macroscopic changes in the mucous membrane of the buccal pouch. Following DMNA administration, tumours developed only in the liver; no tumours developed following the application of DENA. Tumours developed at various sites, including the buccal pouch, in 20 of the 25 hamsters treated with MNU.
mesh_terms: D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D002273:Carcinogens; D002610:Cheek; D006224:Cricetinae; D004052:Diethylnitrosamine; D004128:Dimethylnitrosamine; D005260:Female; D008297:Male; D008647:Mesocricetus; D008770:Methylnitrosourea; D009061:Mouth Mucosa / Q000473:pathology; D009062:Mouth Neoplasms / Q000139:chemically induced*; D009374:Neoplasms, Experimental / Q000139:chemically induced; D010947:Plants, Toxic; D014026:Nicotiana
chemical_list: D002273:Carcinogens; D004052:Diethylnitrosamine; D015127:9,10-Dimethyl-1,2-benzanthracene; D008770:Methylnitrosourea; D004128:Dimethylnitrosamine