Pathogenesis of 1,2-dimethylhydrazine-induced carcinomas in rat intestine. II. Histochemical and ultrastructural characteristics of glycoproteins of 1,2-dimethylhydrazine-induced carcinoma cells.
Two hundred twenty seven lesions of DMH-induced intestinal carcinomas of 68 male Wistar rats were investigated by means of histochemical and electron microscopic properties to study their histogenesis and mucinogenesis. Among the epithelial glycoproteins, surface glycoprotein on the microvilli with glycocalyces was distinguishable from mucin in the cytoplasm based on histochemical staining and ultrastructural findings. From the phenotypic characteristics of glycoproteins, it was suggested that DMH-induced carcinomas could be classified into mucin producing carcinomas composed mainly of cells containing intracellular mucins and non-mucin producing ones. The mucin producing carcinomas consisted of poorly differentiated adenocarcinoma, signet ring cell carcinoma, and mucinous carcinoma presumably resulting from various degrees of differentiation into goblet cells. Their staining attitude varied and cells with neutral mucin, sialomucin and sulphated mucin were observed in the signet ring cell carcinoma. In addition, abnormal synthesis of glycoproteins was observed with ConA-paradox staining and PATS/PB/KOH/PAS. These histochemical properties suggested irregulatory synthesis of glycoproteins in carcinomas. In non-mucin producing carcinomas, glycoproteins were found mainly on the apical surface and contained sialomucin. A deviated differentiation into an absorptive cell could form an intracytoplasmic cyst filled with an aggregation of glycocalyces, so becoming another type of signet ring cell.
D019813:1,2-Dimethylhydrazine; D000230:Adenocarcinoma / Q000378:metabolism; D002288:Adenocarcinoma, Mucinous / Q000378:metabolism; D000818:Animals; D004127:Dimethylhydrazines; D006023:Glycoproteins / Q000378:metabolism*; D006651:Histocytochemistry; D007413:Intestinal Mucosa / Q000378:metabolism; D007414:Intestinal Neoplasms / Q000139:chemically induced / Q000378:metabolism* / Q000648:ultrastructure; D007422:Intestines / Q000648:ultrastructure; D008297:Male; D008763:Methylhydrazines; D008854:Microscopy, Electron; D009077:Mucins / Q000096:biosynthesis; D051381:Rats; D011919:Rats, Inbred Strains; D013194:Staining and Labeling; D014018:Tissue Distribution
D004127:Dimethylhydrazines; D006023:Glycoproteins; D008763:Methylhydrazines; D009077:Mucins; D019813:1,2-Dimethylhydrazine