Cicciarello R, d'Avella D, Albiero F, Mesiti M, Rosati G, Princi P, d'Aquino S, Hayes R L
Institute of Oncology, Faculty of Medicine, University of Messina, Italy.
Brain Inj. 1990 Jan-Mar;4(1):71-6. doi: 10.3109/02699059009026150.
Mechanisms contributing to the rare but consistent neurotoxicity of contrast media currently in clinical use for the radiological examination of the subarachnoid space remain to be isolated. We assessed, by means of the (14C)-2-deoxy-D-glucose (2-DG) autoradiographic method, the effect of three non-ionic, low-osmolar contrast media, namely metrizamide, iopamidol and iohexol, on the local cerebral glucose utilization in the rat brain after intracisternal application. A significant (-30%) global reduction of the brain's metabolic activity occurred following intracisternal metrizamide injection. When compared with the mock-CSF control group the greater relative changes were observed in the supratentorial grey matter structures. In contrast, no significant changes were observed in metabolic brain activity in rats treated intracisternally with iopamidol and iohexol. These findings were consistent with the hypothesis that metrizamide is a competitive inhibitor of human brain hexokinase. The apparent lack of interference on neural tissue metabolism makes the second generation contrast media less neurotoxic and more suitable for neuroradiological subarachnoid investigations in clinical settings. The present experimental work establishes the 2-DG method as a viable laboratory approach to investigate aspects of neuronal dysfunction induced by contrast media.
目前用于蛛网膜下腔放射学检查的造影剂虽罕见但一致的神经毒性作用机制仍有待明确。我们通过（14C）-2-脱氧-D-葡萄糖（2-DG）放射自显影法，评估了三种非离子型低渗造影剂，即甲泛葡胺、碘帕醇和碘海醇，经脑池内注射后对大鼠脑局部葡萄糖利用的影响。脑池内注射甲泛葡胺后，大脑代谢活动出现显著（-30%）的整体降低。与模拟脑脊液对照组相比，幕上灰质结构出现了更大的相对变化。相比之下，脑池内注射碘帕醇和碘海醇的大鼠脑代谢活动未观察到显著变化。这些发现与甲泛葡胺是人类脑己糖激酶竞争性抑制剂的假说一致。第二代造影剂对神经组织代谢明显缺乏干扰，这使其神经毒性更小，更适合临床神经放射学蛛网膜下腔检查。本实验工作确立了2-DG法作为研究造影剂诱导神经元功能障碍相关方面的可行实验室方法。
