title: Histological changes in the submandibular glands of rats after intraductal injection of chemical carcinogens.
abstract: Carcinogens injected into the excretory canal of submandibular gland of Donryu rats revealed the following histologic changes in salivary glands. 20-Methylcholanthrene induced squamous cell metaplasia, fibrosis in the early stages, and "benign lymphoepithelial lesion"-like pattern after 3 months. Dense hyalinization occurred after 4-5 months with so-called "mixed tumor"-like pattern. In the later stages epidermoid carcinoma and fibrosarcoma were observed. 9, 10-Dimethylbenzanthracene caused degenerative change, metaplasia, fibrosis and cell infiltration, and later carcinoma and sarcoma appeared at a high rate. 4-Nitroquinoline-N-oxide led to dense hyalinization and so-called "mixed tumor"-like pattern was observed in many specimens. N-nitroso-N-methyl urethane and N-methyl-N-nitroso-N'-nitroguanidine revealed metaplastic changes, fibrosis and lymphoid infiltration. Scarlet red induced remarkable infiltration and aggregation of lymphoid cells, showing benign "lymphoepithelial lesion"-like pattern.
mesh_terms: D015112:4-Nitroquinoline-1-oxide / Q000008:administration & dosage; D015127:9,10-Dimethyl-1,2-benzanthracene / Q000008:administration & dosage; D008949:Adenoma, Pleomorphic / Q000139:chemically induced / Q000473:pathology*; D000818:Animals; D002273:Carcinogens / Q000008:administration & dosage*; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced / Q000473:pathology*; D004396:Coloring Agents / Q000008:administration & dosage; D005354:Fibrosarcoma / Q000139:chemically induced / Q000473:pathology*; D006391:Hemangioma / Q000139:chemically induced / Q000473:pathology; D007267:Injections; D008297:Male; D008748:Methylcholanthrene / Q000008:administration & dosage; D008769:Methylnitronitrosoguanidine / Q000008:administration & dosage; D009605:Nitrosomethylurethane / Q000008:administration & dosage; D051381:Rats; D012208:Rhabdomyosarcoma / Q000139:chemically induced / Q000473:pathology*; D012468:Salivary Gland Neoplasms / Q000139:chemically induced / Q000473:pathology*; D012469:Salivary Glands; D013363:Submandibular Gland / Q000473:pathology*
chemical_list: D002273:Carcinogens; D004396:Coloring Agents; D008769:Methylnitronitrosoguanidine; D008748:Methylcholanthrene; D015112:4-Nitroquinoline-1-oxide; D015127:9,10-Dimethyl-1,2-benzanthracene; D009605:Nitrosomethylurethane