二甲肼诱导小鼠结肠癌模型的建立及病理学特征检测

Establishment of 1,2-dimethylhydrazine-induced murine colorectal cancer model and pathological feature detection

目的探讨化学致癌剂1,2-二甲肼(DMH)诱导昆明小鼠结肠癌模型的有效性及病理学特性。方法 6~8周龄雄性昆明小鼠随机分为实验组和对照组。实验组小鼠颈背部皮下注射DMH 25 mg/kg,对照组小鼠注射等量生理盐水。每周1次,连续注射12周。期间观察小鼠状态,并分别在给药后12、16、20周和实验终末处死部分小鼠取结肠、肝、肺组织进行大体观察及病理学检测。结果注射DMH 12周后可见部分小鼠肛门红肿溃破,肠壁出现肿瘤结节;16周后实验组有一半小鼠大便溏稀,生成多发性腺癌。20周后实验组小鼠肿瘤进一步发展,并出现明显的肝损伤和肺部转移灶。对照组小鼠无异常表现。结论成功建立了一种二甲肼诱导小鼠产生原发及转移性结肠癌的有效且简便的方法,成瘤有效率达100%。该模型与人类结肠癌在病理学上具有相似特性。

Objective To explore the tumorigenic effect and pathological features of 1,2-dimethylhydrazine（ DMH）-induced colorectal cancer in Kunming mice. Methods 6-8 week old male mice were randomized into the experimental group（ n = 32） and the control group（ n = 8） for subcutaneous injection of DMH（ 25 mg/kg） or saline weekly for 12 weeks,respectively. The mice were sacrificed at 12,16 and 20 weeks after first injection for pathological examination of the colon,liver and lung tissues. Results After injection of DMH for 12 weeks, most mice displayed anal redness and swelling and ulceration, and intestinal wall developed several tumor nodules. Half of the DMH induced-mice started to discharge loose stools and developed multiple colorectal adenomas after 16 weeks. Tumors with malignant characteristic, significant liver injury and lung metastasis were observed in DMH induced-mice at the end of 20 weeks. No obvious pathological changes were found in the control group under the same conditions except for saline treatment.Conclusion A colorectal cancer（ CRC） murine model has been successfully established by using DMH as a chemical carcinogen. The CRC murine model exhibits similar pathological features as human colon cancer.