大鼠脑缺血边缘区代谢物^1H—MRS的研究

1H-MRS STUDY OF THE METABOLITE ON THE BORDER ZONE OF ACUTE CEREBRAL ISCHEMIA

目的 利用不同的局灶性脑缺血模型，评价急性缺血后磁共振质子波谱（１Ｈ－ＭＲＳ）测 定缺血后边缘区脑组织代谢和生物能量变化的时空规律．为判定急性缺血预后，进行有效的 溶栓治疗提供有价值的生物化学信息． 方法 健康Ｓｐｒａｇｕｅ－Ｄａｗｌｙ大鼠９只，雌雄不拘，随机分 为两组． Ａ组（４只），自体血栓栓塞１ｈ； Ｂ组（５只），线栓法栓塞１ｈ．分别于栓塞后３０、４０、５０、６０ ｍｉｎ进行１Ｈ－ＭＲＳ检查，相对含量分析兴趣区（ｒｅｇｉｏｕｓ ｏｆ ｉｎｔｅｒｅｓｔ，ＲＯＩｓ）氮－乙酰天门冬 氨酸（ＮＡＡ）、胆碱（Ｃｈｏ）和乳酸（Ｌａｃ）等代谢产物的变化．结果 以ＮＡＡ、Ｃｈｏ、Ｌａｃ与磷酸肌 酸和肌酸（ＰＣｒ＋Ｃｒ）的谱峰积分面积比值为判断标准，上述各代谢产物在兴趣区内于缺血后 １ｈ内逐渐下降．其中缺血后６０ｍｉｎ．Ｃｈｏ／（ＰＣｒ＋Ｃｒ）、ＮＡＡ／（ＰＣｒ＋Ｃｒ）及Ｌａｃ／（ＰＣｒ＋Ｃｒ）的比 值与缺血后５０ ｍｉｎ的比值统计学有显著性差异（Ｐ＜０．０５）结论 １Ｈ－ＭＲＳ技术为研究急性 缺血性卒中后脑细胞代谢、生化能量状态提供了一个无创性、直接性、综合性的研究工具．

Objective The use of different models of focal cerebral ischemia to appraise the time-space rules of 1H-MRS on measuring metabolism and energy changes in the post-is- chemia brain tissue provides the clinical doctors with valuable information to judge the prog- nosis and carry out more effective therapy from the biochemical point of view. Methods 9 healthy Sprague-Dawly rats( indiscriminate the sex) was divided into two groups randomly. Group A (4 rats), occluded with self-thrombus for 1 h; Group B (5 rats), occluded with thread-emboli for 1 h. The 1H-MRS was examined in 30, 40, 50, 60 mm after occlusion re- spectively, and the metabolic changes of NAA, Cho and L.ac in the regions of interest in partly-fixed quantity were analyzed. Results Set the resonance intregrated area ratio of NAA, Cho, Lac to Pcr+Cr as the criterion, the values of all the metabolites declined gradu- ally within 1 h after ischemia. Especially, the ratio of Cho/ (Pcr + Cr)、 NAA/ ( Pcr + Cr) and Lac/(Pcr+ Cr)in 60 mm has significant difference from that in 50 mm (P<0.05). Conclu- sions .Magnetic Resonance Proton Spectroscopy is a good research tool, which is straight- forward, comprehensive and no damage, for the study of cellular metabolism and the status of the biochemical energy in acute ischemia stroke.