局灶脑缺血区星形胶质细胞可塑性变化的实验研究

AN EXPERIMENTAL STUDY OF PLASTICITY OF ASTROCYTES IN FOCAL ISCHEMIC CEREBRAL REGION

为了探索星形胶质细胞在慢性局灶脑缺血区的分布以及形态和数量变化的时期 ,进而探讨其在脑缺血灶恢复中的作用 ,本研究运用免疫组织化学技术对大鼠进行了研究。结果证明 :胶质纤维酸性蛋白阳性星形胶质细胞在脑梗塞灶的周围发生肥大和增生性改变 ,其突起的变化尤为显著 ;粗大的突起呈纤维状 ,并相互交织呈密集的网 ,其末端向脑梗塞灶的中央延伸。其变化发生于脑缺血第 1周 ,脑缺血第 2周最显著 ,在 6周的脑缺血期间 ,显示持续性变化。 S- 10 0阳性星形胶质细胞在脑梗塞灶周围区的肥大和增生性变化 ,发生于脑缺血第 3d,并持续到脑缺血 4周 ,其形态学改变没有胶质纤维酸性蛋白阳性星形胶质细胞显著。本研究提示慢性局灶脑缺血诱导星形胶质细胞发生形态学的可塑性变化 。

To explore the time course of alteration for astrocytic distribution, number and morphology in focal ischemic brain, and to test astrocytic effect on ischemic cerebral recovery, immunohistochemical technique was used in the study of 38 SD rats. (1) The GFAP positive astrocytic appearance of hypertrophy and proliferation accurred at 1 w infarction in the peri infarct area and continued to 6w post infarction and it was most remarkable at the time point of 2 w post infarction. (2) GFAP positive as astrocytic processes were more apparent and formed a network, and oriented toward the infarct center from the peri infarction. (3) S 100 positive astrocytic hypertrophy and proliferation occurred at 3 d and continued to 6 w post infarction, but the changes of S 100 positive astrocytes were not so apparent as that of GFAP positive astrocytes. The results indicated that focal cerebral ischemia induced the astrocytic plastic reaction, and showed that astrocytes participated actively in the pathological process of ischemic cerebral recovery. (Figures 2～7 on plate 21)