RESUMO
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. RESULT: 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. CONCLUSION: 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.
Assuntos
1,2-Dimetilidrazina , Neoplasias Colorretais , Ciclo-Oxigenase 2 , Inflamação , Fator de Necrose Tumoral alfa , Animais , 1,2-Dimetilidrazina/toxicidade , Ratos , Neoplasias Colorretais/patologia , Neoplasias Colorretais/induzido quimicamente , Neoplasias Colorretais/metabolismo , Ciclo-Oxigenase 2/metabolismo , Inflamação/induzido quimicamente , Inflamação/patologia , Inflamação/metabolismo , Masculino , Fator de Necrose Tumoral alfa/metabolismo , Mucosa Intestinal/patologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Carcinógenos/toxicidade , Ratos Sprague-Dawley , Focos de Criptas Aberrantes/patologia , Focos de Criptas Aberrantes/induzido quimicamente , Focos de Criptas Aberrantes/metabolismo , Colo/patologia , Colo/metabolismo , Adenocarcinoma/patologia , Adenocarcinoma/induzido quimicamente , Adenocarcinoma/metabolismoRESUMO
OBJECTIVE: The aim of this study is to examine the M1 and M2 macrophages distribution in the rat's colon of DMH-induced inflammation associated colorectal cancer. METHODS: Colon tissue of three groups of 4 rats that induced using 1,2 dimethylhydrazine (DMH) at 30 mg/kg bw every week for 9, 11, and 13 weeks were used. The M1 and M2 distribution was examined by using antibody anti iNOS for M1 and anti-CD163 for M2 with immunohistochemistry method. The data was presents in figure and table in the form of percentage. RESULT: M1 macrophage was found in all groups in the low distribution level (25% - 50%), while M2 macrophage was observed in all groups with 100% distribution. In the longer period of DMH induction, M2 macrophages was distributed more abundant. CONCLUSION: All of the rat's colon showing chronic inflammation that led to the tumorigenesis.
