实验性大鼠颅脑损伤后兴奋性氨基酸及脑血流量的变化研究

Changes of Excitatory Amino Acid and Regional Blood Flow after Fluid Percussion Brain Injury in Rat

目的：观察流体冲击致大鼠脑损伤后不同时相点脑组织兴奋性氨基酸(excitatory amino acids, EAA)和局部血流量(regional cerebral blood flow, rCBF)的变化，及它们在脑损伤和继发性脑损伤中的作用。方法：用流体冲击装置制作中度脑损伤，氨基酸微量分析系统检测谷氨酸(glutamate, Glu)和天门冬氨酸(aspartate, Asp)含量，氢清除法检测大脑局部血流量。结果：中度脑损伤后rCBF明显低于伤前和正常对照组；脑组织Glu、Asp的含量在伤后30min即可见明显增加，1h有所回落，2h又有所升高，4h至6h趋于稳定。结论：结果显示脑损伤后脑血流量的下降可能与氨基酸释放有着一定的关系，氨基酸大量释放可能在脑损伤和继发性脑损伤中起着主要作用。

Objective: To elucidate the relationship between changes of excitatory amino acids and regional cerebral blood flow (rCBF) and study the role of them in the brain injury and secondary brain damage. Methods: The traumatic brain injury model of rat was made by the fluid percussion device. The contents of aspartate (Asp) and glutamate (Glu) were detected by micro-analyzer. rCBF was detected by means of the hydrogen clearance method. Results: The contents of Asp and Glu were significantly increased and the level of rGBF was markedly lower than that of the pre-injury and control. There was no difference between the percussion site and contra-lateral site. Conclusion: The experiment showed that there was remarkable relative between the content of EAA and the level of rCBF. EAA might play an important role in the brain and secondary brain damage.