title: Tumor induction in the glandular stomach of rats after oral administration of a single or a few doses of N-methyl-N'-nitro-N-nitrosoguanidine during the newborn period.
abstract: When N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) was orally intubated to conventional newborn rats by the catheter technique, the rats were found with tumors almost exclusively developed in the glandular stomach, mostly until 280 days after the first intubation. Tumor incidence was about 50% in both sexs of rats that survived the intubation of a single dose of MNNG in rats of less than 24 hr after birth and almost 100% in both sexes of rats that survived the intubation of three consecutive daily doses of MNNG on 5th day after birth. Out of 52 rats treated with MNNG, 40.4% developed carcinomas (20 adenocarcinomas and 1 squamous cell carcinoma), three of them having metastatic lesions. The predilective localization of tumors in the glandular, especially fundic, portion of the stomach, might be attributed to the use of newborns and to the catheter technique devised here.
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced*; D000284:Administration, Oral; D000818:Animals; D000831:Animals, Newborn; D002294:Carcinoma, Squamous Cell / Q000139:chemically induced*; D005260:Female; D007890:Leiomyosarcoma / Q000139:chemically induced; D008297:Male; D008769:Methylnitronitrosoguanidine / Q000008:administration & dosage*; D009374:Neoplasms, Experimental / Q000139:chemically induced; D051381:Rats; D013270:Stomach / Q000473:pathology; D013274:Stomach Neoplasms / Q000139:chemically induced* / Q000473:pathology
chemical_list: D008769:Methylnitronitrosoguanidine