title: Zinc deficiency and methylbenzylnitrosamine-induced esophageal cancer in rats.
abstract: Dietary zinc deficiency increases the incidence of and shortens the lag time for induction of esophageal tumors in rats by methylbenzylnitrosamine (MBN). Groups of control and zinc-deficient outbred Charles River CD rats were given 24, 17, 8, or 4 doses of MBN, administered twice weekly by intragastric intubation at doses of 2 mg/kg body weight. Between 58 and 93 days after the beginning of treatment, all rats were killed and examined. The frequency of esophageal tumors in the zinc-deficient groups was significantly higher than in the corresponding control groups. Following ip injection of [methyl-14C]MBN, DNA and RNA of esophagus and liver were more noticeably labeled than kidney, lung, and small intestine, which exhibited only modest labeling. In vitro incubation with [14C]MBN of tissue slices from esophagus, liver, kidney, and small intestine produced similar results. This pattern correlates well with the results of our studies of MBN-induced esophageal tumorigenesis.
mesh_terms: D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000209:etiology*; D004247:DNA / Q000378:metabolism; D004128:Dimethylnitrosamine / Q000031:analogs & derivatives; D004938:Esophageal Neoplasms / Q000209:etiology*; D004947:Esophagus / Q000378:metabolism; D066298:In Vitro Techniques; D008099:Liver / Q000378:metabolism; D008297:Male; D009374:Neoplasms, Experimental / Q000209:etiology; D009602:Nitrosamines / Q000378:metabolism; D012313:RNA / Q000378:metabolism; D051381:Rats; D013997:Time Factors; D015032:Zinc / Q000008:administration & dosage / Q000172:deficiency*
chemical_list: D009602:Nitrosamines; D012313:RNA; D004247:DNA; C014707:nitrosobenzylmethylamine; D015032:Zinc; D004128:Dimethylnitrosamine