Munekata K, Hossmann K A
Stroke. 1987 Mar-Apr;18(2):412-7. doi: 10.1161/01.str.18.2.412.
Adult male gerbils were submitted to 5-minute cerebral ischemia by bilateral carotid artery occlusion. At the end of ischemia and at various recirculation times ranging from 15 to 120 minutes, brains were frozen in situ and the regional distribution of ATP, glucose, and tissue pH was studied on coronal cryostat sections by bioluminescent and fluoroscopic techniques. During ischemia ATP was completely depleted, glucose decreased to less than 10% of control, and regional tissue pH decreased from 7.04-7.09 to about 6.0. After the beginning of recirculation tissue pH and the regional content of metabolites exhibited a triphasic course. After 15 minutes pH returned to or even above normal, and ATP- and glucose-induced bioluminescence normalized. However, there was a secondary deterioration of both tissue acidosis and the metabolic state after 30 minutes. After longer recirculation times changes again improved and returned to normal within 2 hours. These changes were similar in all brain regions with the exception of the CA1 sector of the hippocampus, where the transient normalization of tissue pH was absent after 15 minutes of recirculation. This finding is in line with the previously observed microcirculatory insufficiency of this area and demonstrates that the CA1 sector of the hippocampus suffers more pronounced postischemic acidosis than other less vulnerable regions of the brain.
成年雄性沙鼠通过双侧颈动脉闭塞接受5分钟的脑缺血。在缺血结束时以及在15至120分钟的不同再灌注时间，将大脑原位冷冻，并通过生物发光和荧光技术在冠状低温切片上研究ATP、葡萄糖和组织pH的区域分布。缺血期间，ATP完全耗尽，葡萄糖降至对照值的不到10%，区域组织pH从7.04 - 7.09降至约6.0。再灌注开始后，组织pH和代谢物的区域含量呈现三相变化过程。15分钟后，pH恢复到甚至高于正常水平，ATP和葡萄糖诱导的生物发光恢复正常。然而，30分钟后组织酸中毒和代谢状态出现二次恶化。再灌注时间更长时，变化再次改善并在2小时内恢复正常。除海马体的CA1区外，所有脑区的这些变化相似，在再灌注15分钟后，CA1区组织pH没有出现短暂正常化。这一发现与该区域先前观察到的微循环功能不全一致，并表明海马体的CA1区比大脑其他较不易受损的区域遭受更明显的缺血后酸中毒。
