Juurlink B H, Chen Y, Hertz L
Saskatchewan Stroke Research Centre, College of Medicine, University of Saskatchewan, Canada.
Can J Physiol Pharmacol. 1992;70 Suppl:S344-9. doi: 10.1139/y92-281.
Mouse astrocytes were subjected to in vitro models of ischemia (hypoxia with or without substrate deprivation, excess potassium, or elevated glutamate). Three hours of hypoxia alone or with substrate deprivation had little effect upon the morphology of astrocytes but did cause disaggregation of polyribosomes. Excess (12-50 mM) potassium added (as KCl) to a normal isotonic medium also caused no swelling; it did, however, cause a shrinkage of cell volume. When 50 mM potassium was substituted for a similar amount of sodium, marked swelling occurred. Swelling of astrocytes was also seen after addition of glutamate (50 microM to 1 mM) to the culture medium. These results show that ischemia per se does not result in astrocytic swelling; rather, microenvironmental alterations such as rising glutamate levels and changes in the sodium/potassium ratios result in astrocytic swelling. We conclude that one can use astrocytes in culture to dissect out the mechanisms that cause postischemic alterations in astrocytes in vivo.
将小鼠星形胶质细胞置于体外缺血模型（伴有或不伴有底物剥夺、过量钾或谷氨酸升高的缺氧环境）中。单独缺氧3小时或伴有底物剥夺对星形胶质细胞的形态影响不大，但会导致多核糖体解聚。向正常等渗培养基中添加过量（12 - 50 mM）的钾（以氯化钾形式）也不会导致细胞肿胀；然而，它确实会导致细胞体积缩小。当用50 mM钾替代等量的钠时，会出现明显的肿胀。向培养基中添加谷氨酸（50 μM至1 mM）后也可见星形胶质细胞肿胀。这些结果表明，缺血本身不会导致星形胶质细胞肿胀；相反，诸如谷氨酸水平升高和钠/钾比值变化等微环境改变会导致星形胶质细胞肿胀。我们得出结论，人们可以在培养中使用星形胶质细胞来剖析体内导致星形胶质细胞缺血后改变的机制。
