title: Tumor-bearing depresses distant mast-cell-mediated mitogenesis.
abstract: A methylcholanthrene-induced sarcoma grafted subcutaneously in rats was used in early transplantation generations. Tumor-bearing rats showed weight loss compatible with cachexia. Healthy rats of the same age served as controls. In tumor-bearing rats the basal mesenteric proliferation was unaffected whereas the strictly mast-cell-mediated hyperproliferative reaction in the mesentery was significantly reduced after intraperitoneal injection of the mast-cell-secretagogue compound 48/80, as judged from specific DNA activity and mitosis counting. However, in mesentery and peritoneal lavage the number of mast cells, their histamine-releasing capacity, and their content of histamine, 5-hydroxytryptamine and heparin were unaffected by tumor-burden. The findings suggest the presence of a tumor-associated systemic factor of unknown nature which interferes with the biochemical events leading to the mast-cell-dependent mitogenesis. Since this mitogenic reaction may normally compensate for injury at the cellular level it is questioned whether the decreased mast-cell-dependent proliferation in tumor-bearing is a component of cachexia.
mesh_terms: D000818:Animals; D002100:Cachexia / Q000209:etiology; D008297:Male; D008407:Mast Cells / Q000502:physiology*; D008643:Mesentery / Q000473:pathology; D008748:Methylcholanthrene; D008938:Mitosis; D009368:Neoplasm Transplantation; D051381:Rats; D011919:Rats, Inbred Strains; D012513:Sarcoma, Experimental / Q000139:chemically induced / Q000150:complications / Q000473:pathology*
chemical_list: D008748:Methylcholanthrene