Effect of Intestinal Flora on Megaenteron of Mice

J-STAGE
  • ITOH Kikuji
    Animal Physiology Laboratory, The Institute of Physical and Chemical Research
  • MAEJIMA Kazuyoshi
    Animal Physiology Laboratory, The Institute of Physical and Chemical Research
  • UEDA Katsumoto
    Animal Physiology Laboratory, The Institute of Physical and Chemical Research
  • FUJIWARA Kôsaku
    Animal Physiology Laboratory, The Institute of Physical and Chemical Research

抄録

CF # 1 germfree (GF) and conventional (CV) mice as well as offspring of conventionalized GF (GF-CV) mice were orally inoculated with Escherichia coli 0115a, c : K (B), a causative agent of megaenteron in mice. Although CV and GF mice showed no clinical signs and survived, all of the GF-CV mice died with diarrhea by day 14 after inoculation. Thickened wall of the large intestine, microscopically showing proliferation of crypt type cells, was seen in GF and GF-CV mice but not in CV mice. In addition, in GF-CV mice, hemorrhage and severe erosion with marked inflammatory reactions were observed. While the inoculated E. coli could not colonize in CV mice, a level of 108 cells/g feces was maintained in GF mice from day 1 after inoculation to the end of examination (on day 28) and in GF-CV mice from day 5 to the time of death. Newly prepared germfree (GF-CV-GF) mice obtained hysterectomy from GF-CV mice showed a low sensitivity as comparable to that in GF mice. On the other hand, ex-germfree mice produced by oral administration of feces of GF-CV mice showed severe infection as comparable to that seen in GF-CV mice. These results suggest that the intestinal flora may play roles both on protecting from the infection of pathogenicE.. coli and on enhancing the infection.

収録刊行物

詳細情報 詳細情報について

問題の指摘

ページトップへ