Topical carcinogenesis by N-methyl-N-nitrosourea in Syrian hamster cheek-pouch and oral mucosa.
Pouches of weanlings were painted 3 times a week for 4 weeks with 0.5 per cent NMU in acetone, using a technique designed to localize oncogenesis. Ventral lingual mucosa was painted at the same time. Premalignant, dysplastic lesions or carcinomas arose in pouches of 88 per cent of animals that survived from 8 to 54 weeks, but the majority of these lesions were not localized to the painted area. Biliary hyperplasia, papillomas of the forestomach and abnormalities of the incisor teeth were found in a small number of animals. These changes suggested that systemic absorption of NMU had occurred. No lesions were induced beneath the tongue but occasional premalignant and malignant changes were found in other parts of the mouth.
D000042:Absorption; D000818:Animals; D002610:Cheek; D006224:Cricetinae; D005260:Female; D008297:Male; D008647:Mesocricetus; D008770:Methylnitrosourea / Q000378:metabolism / Q000633:toxicity*; D009061:Mouth Mucosa / Q000187:drug effects; D009062:Mouth Neoplasms / Q000139:chemically induced; D009369:Neoplasms / Q000139:chemically induced*; D009607:Nitrosourea Compounds / Q000633:toxicity*; D010212:Papilloma / Q000139:chemically induced
D009607:Nitrosourea Compounds; D008770:Methylnitrosourea