title: Fine structure of experimental canine gastric carcinoma, with special reference to signet ring cells.
abstract: Fine structure of poorly differentiated adenocarcinoma selectively induced in the canine stomach by a low concentration of N-ethyl-N'-nitro-N-nitrosoguanidine was studied with special reference to the so-called signet ring cells. These cells were electron microscopically classified into two groups: 1) mucin-containing cells and 2) intracellular microcyst cells. The cytoplasm of mucin-containing cells was packed with fused large and low electrondense secretory granules. In another type of signet ring cells, there were intracellular microcysts with microvilli on the internal surface. A comparison of canine and human signet ring cells revealed a close resemblance in the fine structure. Canine gastric carcinoma should be a good model for human gastric carcinoma therapeutics.
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced / Q000648:ultrastructure*; D000818:Animals; D002273:Carcinogens; D002467:Cell Nucleus / Q000648:ultrastructure; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004285:Dogs; D005260:Female; D008297:Male; D008769:Methylnitronitrosoguanidine / Q000031:analogs & derivatives; D009374:Neoplasms, Experimental / Q000139:chemically induced / Q000648:ultrastructure; D013274:Stomach Neoplasms / Q000139:chemically induced / Q000648:ultrastructure*
chemical_list: D002273:Carcinogens; D008769:Methylnitronitrosoguanidine; C013525:ENNG