缺氧与复氧对星形胶质细胞水通道蛋白-9表达的影响

Influence of hypoxia-reoxygenation on expression of aquaporin-9 in cultured astrocytes

目的探讨体外培养星形胶质细胞缺氧及复氧后水通道蛋白-9(AQP9)表达的变化特点及其所起的作用。方法取生后2d的Wistar大鼠大脑皮层进行星形胶质细胞纯培养,缺氧时间分别为:12、24、48h,并取缺氧24h后复氧12、24、48h的细胞进行存活率、乳酸脱氢酶活性的测定,采用免疫细胞化学方法检测细胞AQP9的表达。结果缺氧组及复氧组的星形胶质细胞死亡数与对照组相比无明显变化,缺氧和复氧后乳酸脱氢酶活性亦无明显改变(P(0.05),缺氧组细胞AQP9表达较对照组增高,并随缺氧时间延长而明显增高(P<0.05),复氧后24h内AQP9表达逐渐下降,24h后AQP9表达仍未恢复正常水平。结论星形胶质细胞对缺氧较为耐受,缺氧对星形胶质细胞存活能力无明显影响,缺氧引起AQP9的表达上调,而复氧使其表达明显下降。

Objective To investigate the expressions of aquaporin-9（AQP9）and its role in cultured rat astrocytes after exposure to hypoxia-reoxygenation.Methods Rat cerebral cortical astrocytes from 2 days newborn Wistar rats were undergone the pure culture.The hypoxia periods were 12,24,48h.After 24h of hypoxia,the reoxygenated periods were 12,24,48h.We observed the cell viability,the activity of LDH.The reactivity and rules of AQP9 expression of astrocyte to hypoxia-reoxygenation were studied by immunocytochemistry.Results Astrocytes exposed to hypoxia and reoxygenation showed no significant change in cell viability and the activity of LDH than those in the control group.Analysis confirmed that the expression of AQP9 was remarkably increased during hypoxia,up-graduated expression of AQP9 was correlated with hypoxia and time dependent manner（P0.05）.The expression of AQP9 was decreased during reoxygenation for 24h.After cells were reoxygenation for 24h,the expression was not restored to the normal level.Conclusion Astrocytes had the better capacity to tolerate hypoxia.There was no change in cell viability.The experiment showed that hypoxia could increase the levels of AQP9 expression and reoxygenation inhibited the increment of this gene expression.