Project/Area Number |
08457170
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Gastroenterology
|
Research Institution | Oita Medical University |
Principal Investigator |
FUJIOKA Toshio Oita Med.Univ.Internal Medicine Associate Professor, 医学部, 助教授 (90145368)
|
Co-Investigator(Kenkyū-buntansha) |
NISHIZONO Akira Oita Med.Univ.Inf.Dis.Cont.Associate Professor, 医学部, 助教授 (70218155)
KUBOTA Toshihiro Oita Med.Univ.Internal Medicine Research Associate, 医学部, 助手 (30244172)
MURAKAMI Kazunari Oita Med.Univ.Internal Medicine Research Associate, 医学部, 助手 (00239485)
|
Project Period (FY) |
1996 – 1998
|
Project Status |
Completed (Fiscal Year 1998)
|
Budget Amount *help |
¥4,600,000 (Direct Cost: ¥4,600,000)
Fiscal Year 1998: ¥300,000 (Direct Cost: ¥300,000)
Fiscal Year 1997: ¥200,000 (Direct Cost: ¥200,000)
Fiscal Year 1996: ¥4,100,000 (Direct Cost: ¥4,100,000)
|
Keywords | animal model / gastric ulcer / atrophic gastritis / intestinal metaplasia / gastric carcinoma / Mongolian gerbil / 胃癌 / Helicobacter pylori |
Research Abstract |
Helicobacter pylon is classified by IARC/WHO as a definite human gastric carcinogen, despite "inadequate experimental evidence". To obtain direct evidence concerning this relationship, we investigated the histopathological findings of gastric mucosa using a model of H.pylori infection in Mongolian gerbils. The animals were challenged p. o. with H.pylori ATCC-43504 and sacrificed at 1, 2, 3, 6, 12, and 18 months after inoculation for histological examination. The spiral bacteria were observed in the mucus and gastric pits of all infected animals. A severe infiltration of the lamina propria by polymorphonuclear and mononuclear cells was seen 1 month after H.pylori inoculation. The submucosa was infiltrated by mainly mononullear cells with formation of lymphoid follicles 2 and 3 months after inoculation. Gastric ulcer at the pyloric area in proximity to the fluidus, atrophic gastritis and focal intestinal metaplasia in the lesser curvature of the antrum appeared at 6 months after inoculation. Intestinal metaplasia became severe, with dysplasia, after that. At 18 mnoths after H.pylori inoculation, two of five infected animals showed three well-differentiated gastric adenocarcinomas. The uninfected control animals showed no abnormal findings throughout the entire observation period. This study shows gastric carcinogenesis in a H.pylori-infected Mongolian gerbil model and confirms the IARC/WHO report that H.pylori is a definite human gastric carcinogen.
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