【摘要】 本文利用电子显微镜及细胞化学技术研究了沙土鼠脑缺血后不同时间海马组织中钙在亚细胞定位分布的变化。实验结果显示:缺血5分钟后最早期的变化为星形细胞突起水肿,以毛细血管周围细胞水肿最明显,细胞内钙分布未见异常变化;缺血30分钟组多数神经细胞固缩,细胞胞浆、胞核及线粒体内有大量钙沉积,钙的蓄积程度与细胞损伤程度一致。实验提示、脑缺血早期的细胞毒性水肿与钙分布的变化无关,但随后由于钙内流,对细胞产生毒性作用而破坏细胞结构的完整性。本文证明,在这类研究中应用草酸——焦锑酸钾电镜细胞化学技术可以显示形态学与机能科学结合起来的优越性。更多还原

【Abstract】 The distribution of calcium ions in the hippocampus of gerbils at different,times of the ischemia was studied with EM-cytochemistry.The earliest morph-logic change which was the swelling ofastrocytic processes,esreeially those surr-ounding the capillaries,was demonstrated in 5 min of the ischemia,while the calcium content and distribution were normal,In 30 min of ischemia,a lot of the neurons were pyknotic,astroeytic swelling became more prominent,and the structure of the plasmic membrane of astrocytes was destroyed.At this time,there were large amount of calcium deposits in cytoplasm,nuclei and mitochondria in astrocytes as well as the neu-rons.The severity of calcium accumulation was in proportion to 1 that of the cell damage The results suggest that eytotoxie edema at the early stage of ischemia is not related to the change of calcium distribution,whereas calcium influx gradually causes toxic effects damaging the integration of celiular structure.This study also shows the superiority of morphologic studty combined with functional sciences using the technique of Oxalater-Potassium Pyroantimonate EM-cytochemistry更多还原