title: Comparative studies on the production of stomach tumors following the intubation of several doses of N-methyl-N'-nitro-N-nitrosoguanidine in germ-free and conventional newborn rats.
abstract: The present work was undertaken to investigate the possible role of microflora in gastric tumorigenesis by the comparison of tumor production between germ-free and conventional male Wistar rats given the same amount of N-methyl-N'-nitro-N-nitrosoguanidine into the stomach by catheter during the newborn period. Only 29% of germ-free rats treated with 450 microgram/animal that were killed 300 days after the first intubation had tumors in the stomach, whereas 93% of conventional similarly treated rats had such tumors at the same period, suggesting that the microflora might exert a promoting influence upon stomach tumor production.
mesh_terms: D000230:Adenocarcinoma / Q000139:chemically induced* / Q000473:pathology; D000818:Animals; D005856:Germ-Free Life; D008297:Male; D008769:Methylnitronitrosoguanidine; D009374:Neoplasms, Experimental / Q000473:pathology; D051381:Rats; D011919:Rats, Inbred Strains; D013274:Stomach Neoplasms / Q000139:chemically induced* / Q000473:pathology
chemical_list: D008769:Methylnitronitrosoguanidine