Masana Y, Morimoto K, Hayakawa T, Shimizu H, Shimada N, Nii Y, Yoshimine T, Mogami H, Hashimoto T
Department of Neurosurgery, Osaka University Medical School, Japan.
No To Shinkei. 1989 Jul;41(7):687-93.
During progression and recovery of ischemia, extracellular purine catabolites were measured and compared with purine catabolites and adenine nucleotide levels in the tissue. Ischemia was induced by bilateral occlusion of the common carotid arteries in gerbil. Extracellular purine catabolites were sampled by in vivo brain microdialysis technique, and tissue adenine nucleotides and purine catabolites were extracted from in situ frozen and lypholized brain tissue. These metabolites were measured with simple method of isoclatic condition by HPLC system. Ischemia depleted tissue ATP and ADP, whereas AMP and purine catabolites accumulated strikingly. In parallel, extracellular purine catabolites increased as consecutive degradation on the biochemical metabolic pathway in the same animal. Levels of tissue ATP and adenosine normalized in the recovery phase of ischemia immediately. However, extracellular purine catabolites during the recovery are much higher than those during the progression of ischemia. These data indicated extracellular high levels of purine catabolites during the ischemic insult, and especially adenosine as neuromodulator which may turn off spontaneous neuronal activity and exert antiepileptic effects during the recovery rather than the progression of ischemia.
在缺血的进展和恢复过程中，对细胞外嘌呤分解代谢产物进行了测量，并与组织中的嘌呤分解代谢产物和腺嘌呤核苷酸水平进行了比较。通过结扎沙鼠双侧颈总动脉诱导缺血。采用体内脑微透析技术采集细胞外嘌呤分解代谢产物，从原位冷冻和冻干的脑组织中提取组织腺嘌呤核苷酸和嘌呤分解代谢产物。这些代谢产物通过高效液相色谱系统在等度条件下的简单方法进行测量。缺血使组织中的ATP和ADP减少，而AMP和嘌呤分解代谢产物显著积累。同时，在同一动物中，随着生化代谢途径上的连续降解，细胞外嘌呤分解代谢产物增加。在缺血恢复阶段，组织ATP和腺苷水平立即恢复正常。然而，恢复过程中的细胞外嘌呤分解代谢产物远高于缺血进展过程中的水平。这些数据表明，在缺血损伤期间细胞外嘌呤分解代谢产物水平较高，尤其是腺苷作为神经调节剂，可能在缺血恢复而非进展过程中关闭自发神经元活动并发挥抗癫痫作用。
