大鼠脑C6胶质瘤组织的1H磁共振波谱

目的采用高场强高分辨磁共振波谱仪在体观察正常大鼠脑组织及种植C6胶质瘤的代谢及生化改变,以评价高分辨1H磁共振波谱在大鼠脑肿瘤模型中的应用价值. 方法将20只体质量200～250 g左右的Wister大鼠分为两组. 正常组:5只;肿瘤组15只,在右尾状核接种C6细胞. 肿瘤组动态观察MR平扫及动态增强扫描的改变,并于接种C6细胞后15～20 d采用点分辨波谱法(PRESS: point resolved spectroscopy)行1H磁共振波谱检测. 结果正常组脑组织1H波谱可检出N-乙酰门冬氨酸(NAA),胆碱类化合物(Cho),肌酸和磷酸肌酸(Cr+PCr)、谷氨酸和谷胺酰胺(Glu+Gln),脂质(Lip),乳酸(Lac). C6胶质瘤NAA较正常组明显降低,NAA/Cho较正常组明显降低(P<0.01),NAA/Cr较正常组也明显下降(P<0.01),Cho/Cr明显升高(P<0.05),Lac升高. 结论高场强磁共振波谱仪可以准确观察在体大鼠脑组织及C6胶质瘤的1H磁共振波谱. 高分辨1H磁共振波谱的改变早于MRI形态改变,能够对肿瘤的早期代谢及生化改变进行监测.

High resolution 1H NMR spectroscopy in rat brain C6 glioma

AIM To evaluate the in vivo metabolism of C6 glioma by using high magnetic field spectrometer and evaluate the practical value of high resolution 1H NMR spectroscopy. METHODS Twenty Wister rats weighting 200 ~ 250 g were divided into two groups. Fifteen rats were implanted with C6 glioma spheroids in right caudate nucleus and the other five were used as controls. Plain MR image and enhanced MRI were performed at intervals. The 1H NMR spectroscopy was performed 15~20 days after the implantation by using point resolved spectroscopy (PRESS) technique. RESULTS The NAA Cho, Cr+PCr, Glu+Gln, Lip and Lac were observed in normal rats. The NAA intensity decreased or disappeared in C6 glioma, NAA/Cho and NAA/Cr ratio decreased obviously ( P <0.01), Cho/Cr increased obviously ( P <0.05), and Lac signal intensity increased. CONCLUSION The high resolution spectrometer can clearly observe in vivo metabolism and biochemical changes of normal rats and C6 glioma spheroids. As the changes in NMR spectroscopy are earlier than those in MRI, high resolution 1H NMR spectroscopy can monitor early changes of tumor metabolism.