大鼠肝肿瘤模型建立及磁共振新技术表现

目的建立大鼠种植性肝肿瘤模型,并研究磁共振影像学表现。方法(1)选择体重约250~300g SD大鼠50只,将肿瘤细胞混悬液种植到大鼠肝叶中;(2)肝肿瘤形成后进行磁共振各序列(MRI,DWI,MRS,PWI)检查;(3)肿瘤组织送病理学检查及电镜检查;(4)将磁共振与病理学检查对照分析。结果(1)大鼠肝肿瘤种植成功率100%;(2)HE染色肿瘤组织呈岛状,内见小片坏死灶,血管内皮细胞生成因子(VEGF)及增殖细胞核抗原(PCNA)染色表达阳性,CD34染色微血管数增多,电镜清晰显示肿瘤的超微结构;(3)T1WI呈低信号,T2WI及DWI呈高信号,表观弥散系数(apparent diffusion coefficient,ADC)减低;胆碱(Choline,Cho)、肌酸(Creatine,Cr)、谷氨酸(Glutamate,Glx)、乳酸(Lactate,Lac)及脂质(Lipid,Lip)峰均明显增高;PWI示肿瘤血供丰富,最大相对信号强度增减率(MRSI)明显增高,并与VEGF及CD34呈正相关关系。结论肿瘤细胞混悬液种植可成功制备大鼠肝肿瘤模型,磁共振成像检查肿瘤有特异性表现。

Model Establishment of Rat Liver Tumor and Its MR Imaging Features

Objective To establish the model of rat liver tumor and to study their MR imaging findings.Methods(1)50 SD rats(body weight 250~300 g)were injected with the suspension of tumor cell in hepatic right or left lobe.(2)Rats were examined with conventional MRI,DWI,MRS,and PWI after tumor growth.(3)The rats were sampled for electronic microscopy and pathology.HE staining,proliferating cell nuclear antigen(PCNA),CD34 and vascular endothelial growth factor(VEGF)staining were done.(4)MRI findings were analyzed in comparison with pathology.Results(1)The successful rate of planting tumor was 100%.(2)The tumor was distributed like island in HE staining because of patchy necrosis in tumor.There were much hyperplasia in PCNA,microvessel density decreasing in CD34 and positive ratio decreasing in VEGF,microstructure were found under electronic microscopy.(3)The tumors were low signal intensity on T1WI,high signal intensity on T2WI and DWI,the value of ADC decreased,the peak of Cho,Cr,Glx,Lac,Lip increaed at MRS,PWI showed that the tumors had rich blood supply and the peak of maximal relative signal increase(MRSI)elevated which were positive relation with CD34 and VEGF.Conclusion The model of rat liver tumor can be established by injecting the suspension of tumor cell,the tumors are of characteristic imaging features.