Abstract：
OBJECTIVE: This study examined the morphological changes in the colonic mucosa and the presence of inflammation in rats induced with 1,2-dimethylhydrazine (DMH) 30 mg/kg BW over 9, 11, and 13 weeks without a latency period.
METHODS: Hematoxylin and eosin staining was performed to assess the morphology and characteristic alteration of the epitheliocytes in the colon. Immunohistochemistry was employed to assess the expression of tumor necrosis factor (TNF)-α and cyclooxygenase-2 (COX-2). The difference in the severity of inflammation and COX-2 expression was examined using one-way analysis of variance. The correlation of COX-2 expression with the severity of inflammation was analyzed using Spearman\'s rank correlation test.
RESULTS: Until week 13, chronic inflammation and non-hyperplastic and hyperplastic aberrant crypt foci occurred. The severity of inflammation gradually shifted from high moderate to low moderate. TNF-α expression was high in all groups; however, COX-2 expression was gradually lower with longer duration of induction, which corresponded with the severity of inflammation.
CONCLUSIONS: DMH induction until week 13 without a latency period caused chronic inflammation without the formation of adenoma or adenocarcinoma. A very strong correlation was established between COX-2 expression and inflammation.
METHODS: Hematoxylin and eosin staining was performed to assess the morphology and characteristic alteration of the epitheliocytes in the colon. Immunohistochemistry was employed to assess the expression of tumor necrosis factor (TNF)-α and cyclooxygenase-2 (COX-2). The difference in the severity of inflammation and COX-2 expression was examined using one-way analysis of variance. The correlation of COX-2 expression with the severity of inflammation was analyzed using Spearman\'s rank correlation test.
RESULTS: Until week 13, chronic inflammation and non-hyperplastic and hyperplastic aberrant crypt foci occurred. The severity of inflammation gradually shifted from high moderate to low moderate. TNF-α expression was high in all groups; however, COX-2 expression was gradually lower with longer duration of induction, which corresponded with the severity of inflammation.
CONCLUSIONS: DMH induction until week 13 without a latency period caused chronic inflammation without the formation of adenoma or adenocarcinoma. A very strong correlation was established between COX-2 expression and inflammation.
摘要：
目的：本研究检查了1,2-二甲基肼（DMH）30mg/kgBW在9、11和13周内诱导的大鼠结肠粘膜的形态学变化和炎症的存在，没有潜伏期。
方法:进行苏木精和伊红染色以评估结肠中上皮细胞的形态和特征性改变。免疫组织化学用于评估肿瘤坏死因子（TNF）-α和环氧合酶-2（COX-2）的表达。使用单向方差分析检查炎症严重程度和COX-2表达的差异。采用Spearman秩相关检验分析COX-2表达与炎症严重程度的相关性。
结果：直到第13周，慢性炎症和非增生和增生异常隐窝灶发生。炎症的严重程度逐渐从高中度转变为低中度。TNF-α在所有组中的表达都很高；然而，随着诱导时间的延长，COX-2表达逐渐降低，这与炎症的严重程度相对应。
结论：DMH诱导至第13周，无潜伏期，引起慢性炎症，无腺瘤或腺癌的形成。在COX-2表达和炎症之间建立了非常强的相关性。
方法:进行苏木精和伊红染色以评估结肠中上皮细胞的形态和特征性改变。免疫组织化学用于评估肿瘤坏死因子（TNF）-α和环氧合酶-2（COX-2）的表达。使用单向方差分析检查炎症严重程度和COX-2表达的差异。采用Spearman秩相关检验分析COX-2表达与炎症严重程度的相关性。
结果：直到第13周，慢性炎症和非增生和增生异常隐窝灶发生。炎症的严重程度逐渐从高中度转变为低中度。TNF-α在所有组中的表达都很高；然而，随着诱导时间的延长，COX-2表达逐渐降低，这与炎症的严重程度相对应。
结论：DMH诱导至第13周，无潜伏期，引起慢性炎症，无腺瘤或腺癌的形成。在COX-2表达和炎症之间建立了非常强的相关性。
