Budget Amount *help |
¥1,700,000 (Direct Cost: ¥1,700,000)
Fiscal Year 1995: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1994: ¥900,000 (Direct Cost: ¥900,000)
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Research Abstract |
This study was performed to know a reliable test for premalignant jesions (dysplasia) in the colonic wall in a model of experimental colitis and colonic tumors induced in Wistar male rats by the feeding of dextran sulfate sodium (DSS). For this purpose, histochemical and immunocytochemical methods were applied to identify mucus reacted with each HID-AB,PAS,and lectin stain and to detect premalignant colonic epithlium with ulex europeus agglutinin biding, and immunocytochemical procedures were applied to try to identify c-myc, a growth factor, TGF alpha, and TGF beta in colonic cancer developed in DSS-induced colitis. As experimental colitis may be valuable in the investigation of the relationship between inflammation and dysplasia, we tried to identify expression of mRNA of proinflammatory cytokines, IL-1alpha and TNF alpha, and a neurogenic proinflammatory factor, substance P (SP) in the colonic wall of colitic rats. Results and conclusion are follow : (1) chemical component of mucus reacted with HID-AB,PAS and lectin stain, and ulex europeus agglutinin biding in dysplasia were not markedly different from those in inflammed area of the colitic wall. (2) immunocytochemistry of c-myc, TGFalpha, and TGF beta revealed very weak reactions in colonic tumors. (3) overexpression of mRNA of IL-1alpha and TNFalpha, and suppression of SP mRNA expression were noted in dysplasia and inflammed area of the colitic wall. From these results, it was concluded that marked inflammation (colitis) induced by DSS is an important factor in the development of dysplasia and probably cancer and IL-1, TNF,and SP gene may be involved in the development of the inflammation. Histochemical and immunocytochemical studies are problematic to identify dysplasia and cancer.
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