Effect of Mouse Intestinal Bacteia on Incidence of Colorectal Tumors Induced by 1,2-dimethylhydrazine Injection in Gnotobiotic Transgenic Mice Harboring Human Prototype c-Ha-ras Genes

摘要

We produced transgenic (Tg) gnotobiotic (GB) mice carrying human prototype c- Ha-ras genes and compared the incidence of colorectal tumors induced by 1,2- Dimethylhydrazie (DMH) injection. At 7 to 11 weeks of age, germfree (GF) CB6F-1Tg Hras2 Mice were inoculated with various mouse fecal suspensions or mixtures of bacteria isolated Form mouse feces. Tree weeks after bacterial inoculation, DMH was administered by Subcutaneous injection at 20 mg per kg body weight for 20 weeks.