title: [Mammary gland tumor induction in rats by N-nitroso-N-methylurea and N-methyl-N1-nitro-N-nitrosoguanidine].
abstract: Cancer of the mammary gland was induced in female non-inbred rats under the local effect of N-nitroso-N-methylurea (NMU) and N-methyl-N-nitro-N-nitrosoguanidine (MNNG). During 10 weeks 2.5 mg of the substance in 0.2 ml of saline was injected in the region of the third mammary gland once a week. Under NMU exposure a primary tumor arose 3 months following the initiation of the experiment, the average latent period being 5.8 months, the incidence rate--76.7%. All tumors of this series were adenocarcinomas, in 5 cases there were noted sites of fibroadenomatosis with malignification along the tumor node margins. MNNG produced a primary tumor at the 7th month of the experiment, an average latent period--8.3 months, the incidence rate--56.7%. Tumors were mostly adenocarcinomas.
mesh_terms: D000818:Animals; D005260:Female; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced* / Q000473:pathology; D008769:Methylnitronitrosoguanidine; D008770:Methylnitrosourea; D009607:Nitrosourea Compounds; D051381:Rats; D013997:Time Factors
chemical_list: D009607:Nitrosourea Compounds; D008769:Methylnitronitrosoguanidine; D008770:Methylnitrosourea
vernacular_title: Induktsiia opukholeĭ molochnykh zhelez u krys N-nitrozo-N-metilmochevinoĭ i N-metil-N1-nitro-N-nitrozoguanidinom.