title: Biochemical composition of edge and center of malignant hamster insulinoma.
abstract: The purpose of this study was to determine if there is a difference in the biochemical composition of the edge of a tumor and the center of a tumor. There was a greater concentration of histamine in the edge (mean +/- SEM, 9.3 +/- 1.2 pmole/mg of wet weight) than in the center (3.6 +/- 0.4 pmole/mg of wet weight) of a transplantable golden hamster insulinoma. There was, however, no difference in the concentration of norepinephrine, protein, DNA, or phosphate, or in the activity of the enzymes, monoamine oxidase, catechol-O-methyltransferase, L-dopa decarboxylase, or 5'-nucleotidase in the edge or in the center of the tumor. Using chemical analysis and autoradiography, there was a comparable incorporation of tritiated thymidine in the edge and in the center of the tumor.
mesh_terms: D007516:Adenoma, Islet Cell / Q000378:metabolism*; D000818:Animals; D001345:Autoradiography; D006224:Cricetinae; D004247:DNA / Q000096:biosynthesis; D007340:Insulinoma / Q000201:enzymology / Q000378:metabolism*; D008647:Mesocricetus; D009368:Neoplasm Transplantation; D010190:Pancreatic Neoplasms / Q000201:enzymology / Q000378:metabolism*; D013936:Thymidine / Q000378:metabolism; D014018:Tissue Distribution
chemical_list: D004247:DNA; D013936:Thymidine