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目的 通过建立SD大鼠C6原位胶质瘤模型并进行DCE-MRI扫描,探讨DCE-MRI相关定量参数与肿瘤乏氧状态之间的相关性.方法 取50只雄性SD大鼠建立C6胶质瘤模型,于造模成功后的第2周、3周、4周行包括T1WI、T2WI、DCE-MRI在内的磁共振扫描,并于DCE-MRI扫描的第6期开始由股静脉团注小分子顺磁性钆类对比剂,共行100期连续动态增强扫描,所得数据经后处理软件分析得到包括DCE-MRI各定量参数以及伪彩图.每次扫描结束后随机选取14只SD大鼠行心脏灌注取脑,所得标本行HE染色及HIF-1α免疫组织化学染色检测,得到不同区域HIF-1α表达情况,并将各定量参数与免疫组织化学结果进行Pearson相关性分析.结果 DCE-MRI成像中,肿瘤实性成分显示为明显渐进性强化,伪彩图显示为高灌注,而邻近坏死区域显示为无强化或仅轻度强化,伪彩图显示为低灌注.随着观察时间的延长,SD大鼠C6胶质瘤模型2周、3周、4周的Ktrans值分别为(0.09±0.04)/s、(0.19±0.09)/s、(0.13±0.06)/s,Ve值分别为1.09 ±0.28、0.76 ±0.33、0.48 ±0.20,Kep值分别为(0.10 ±0.04)/s、(0.26 ±0.85)/s、(0.41 ±0.26)/s;HIF-1α评分分别为2.00±0.94、6.50 ±3.15、3.50±1.65.第2周大鼠胶质瘤模型定量参数值与HIF-lα阳性率之间无明显相关性(P值均＞0.05);第3周、4周定量参数Ktrans、Ve值与HIF-lα之间存在负相关性(第3周相关系数Ktrans:r=-0.79;Ve:r=-0.82.第4周相关系数Ktrans:r=-0.63;Ve:r=-0.69,P值均＜0.05).Kep值与HIF-1α之间始终无相关性.结论 SD大鼠C6胶质瘤模型不同时期的DCE-MRI定量参数与肿瘤内部的乏氧状态相关性不同,通过DCE-MRI技术获得的定量参数能够评价大鼠原位胶质瘤模型的乏氧状态.“,”Objective To establish the C6 brain glioma model in SD rats and use DCE-MRI to scan them,and to investigate the correlation between DCE-MRI quantitative parameters and tumor hypoxia state.Methods T1 WI,T2WI,and DCE-MRI was performed for second,3 and 4 week in SD rats with C6 glioma model after successful modeling.A total of 100 consecutive dynamic contrast-enhanced scans were performed and in the sixth phase of DCE-MRI scan,small molecule paramagnetic gadolinium contrast agent was injected into the rats femoral vein.Finally,the software analysed of the quantitative parameters and pseudo color data by postprocessing.At the end of each scan,l4 SD rats were randomly selected to receive cardiac perfusion and removal of brain tissue.The obtained samples were detected by HE staining and HIF-1 α immunohistochemical staining.The correlation between the quantitative parameters and immunohistochemical results was analyzed by Pearson.Results In DCE-MRI imaging,the solid components of tumors showed obvious progressive enhancement,and the corresponding pseudo color display for high perfusion,but the adjacent areas of necrosis showed no enhancement or only mild enhancement and the corresponding pseudo color display for low perfusion.With the prolongation of observation time,the 2W,3W,and 4W Ktrans value were (0.09 ±0.04)/s,(0.19 ±0.09)/s,(0.13 ±0.06)/s,Ve value were 1.09 ±0.28,0.76 ±0.33,0.48 ±0.20,Kep value were (0.10 ±0.04)/s,(0.26 ±0.85)/s,(0.41 ± 0.26)/s,and the HIF-1 α staining score were 2.0 ± 0.94,6.5 ± 3.15,3.5 ± 1.65.There was no statistical correlation between the quantitative parameters and HIF-1 α expression in the glioma model of second week rats (P ＞ 0.05).The 3W,4W glioma model quantitative parameters Ktrans,Ve value and HIF-1α expression was negatively correlated (the correlation coefficient of 3W was Ktrans:r =-0.79,Ve:r =-0.82;and the correlation coefficient of 4W was K:r =-0.63,Ve:r =-0.69,P value were ＜ 0.05).There was no statistical correlation in Kep and HIF-1α expression.Conclusion The quantitative parameters of DCE-MRI in different periods were different from the hypoxic state in the tumor and they can be used to evaluate the hypoxic status of SD rat model of glioma in situ.