基于多因素诱导的大鼠肝癌综合模型的构建

Establishment of a Comprehensive Model of Rat Liver Cancer Induced by Multiple Factors

目的:在化学试剂二乙基亚硝胺(diethylnitrosamine,DEN)诱发肝癌模型的基础上,联合高脂高糖饮食、农药污染及湿热环境三因素叠加的作用,探索建立一种符合临床多因素发病机制的大鼠肝癌综合模型。方法:采用6 w龄SPF级SD大鼠,按体质量随机分为正常对照组、DEN基础模型组、综合模型高剂量组、综合模型低剂量组。正常对照组间歇皮下注射生理盐水,DEN基础模型组间歇皮下注射DEN,综合模型组间歇皮下注射DEN+不同剂量农药暴露+不同剂量高脂高糖饮食+不同时间湿热环境处理。试验中每天观察大鼠的摄食、饮水、毛色、精神状态及活动情况,每周称体质量。试验第13、18 w时进行肝脏超声检查,第19 w试验结束时进行大鼠肝功能及肿瘤分子标志物水平测定,观察肝脏形态及组织病理学变化。结果:正常对照组大鼠摄食活动正常,毛发自然有光泽;造模各组大鼠则逐渐出现不同程度的消瘦、毛发枯槁、活动减少等现象;超声检查显示各模型组大鼠肝脏肿大并出现大小不一的结节;与正常对照组比较,各模型组大鼠肝脏指数、肝功能指标及肿瘤分子标志物含量等显著升高(P<0.01);与DEN基础模型组比较,综合模型高剂量组的肝脏指数、谷草转氨酶(Aspertate aminotransferase,AST)及甲胎蛋白(Alphafetoprotein,AFP)等含量明显升高(P<0.05或P<0.01),其肝脏组织形态学也呈现更明显的癌变特征。结论:本研究建立的多因素联合诱导的肝癌动物模型,病理指标突出,肝组织癌变特征明显,相对于化学试剂诱癌模型更贴近临床实际。

Objective:To establish a comprehensive model of rat liver cancer conforming to clinical pathogenesis by incorporating high-fat and high-sugar diet,pesticide pollution,and high temperature and high humidity environment on the basis of the liver cancer model induced by diethylnitrosamine(DEN).Methods:SD rats(SPF,6 weeks old)were randomLy divided into control group,DEN basic model group,high-dose comprehensive model group,and low-dose comprehensive model group according to body weight.The control group was given normal saline at intervals(sc).The DEN basic model group was treated with DEN solution at intervals(sc),and the comprehensive model groups were treated with DEN solution+different doses of pesticide exposure+different doses of high-sugar and high-fat diet+high temperature and high humidity environment for different durations at intervals(sc).During administration,the rats’appetite,hair color,mental state and behavior change were observed every day,and their body weight was measured every week.Ultrasonic measurement was performed on rat liver at the 13thand 18thweek of the experiment.At the end of the experiment(19thweek),the liver function and tumor markers of the rats were determined,and the morphological and histopathological changes were also investigated.Results:The control group had normal dietary activities and natural,shiny hair color,while the other groups presented various degrees of weight loss,hair loss and decreased activity.Ultrasound measurement found swollen liver with nodules of different sizes in all model groups.Compared with the conditions in the control group,the liver indexes,liver function indexes and tumor markers were increased in all model groups(P<0.01).Compared with DEN basic model group,the high-dose comprehensive model group had elevated liver indexes and aspertate aminotransferase(AST)and alphafetoprotein(AFP)levels(P<0.01 or P<0.05),with obvious carcinomatous change in liver tissues.Conclusion:This comprehensive model of rat liver cancer induced by multiple factors highlighted pathological indexes and had distinct cancer characteristics,which was closer to clinical practices than chemical reagents-induced cancer model.