摘要
目的 探讨体外培养星形胶质细胞缺氧再给氧后热休克蛋白 70 (HSP70 )表达的变化特点及其所起的作用。方法 取生后 1～ 2d的新生昆明小鼠大脑皮层进行星形胶质细胞纯培养 ,培养2周左右进行缺氧实验。缺氧时间分别为 0、3、6、12、2 4、48h ,并取缺氧 2 4h后再给氧 0、3、6、12、2 4、48h的星形胶质细胞进行细胞免疫组化、原位杂交 ,观察HSP70表达的变化。结果 原位杂交显示缺氧 3h即有HSP70mRNA的表达 ,6h达高峰 ,12h仍较明显 ,2 4h后逐渐下降 ,48h表达显著降低 ,但仍高于对照组 (即缺氧 0小时组 )。而用免疫组化方法在缺氧后仅能检出少量阳性的HSP70核蛋白。缺氧 2 4h后再给氧也有HSP70mRNA的表达 ,于再给氧 6h达高峰 ,12h逐渐下降 ,同时免疫组化可见应激蛋白HSP70的检出 ,为核内表达 ,于再给氧 12h达高峰。结论 缺氧可引起HSP70mRNA的表达增强 ,直至随后再给氧时才有应激蛋白HSP70的合成 ,HSP70可能对于星形胶质细胞缺氧再给氧引起的损伤具有保护作用。
Objective To investigate the expression of heat shock protein 70(HSP70) mRNA and the immunoreactivity in cultured mouse astrocytes after exposure to hypoxia/reoxygenation. Methods Mouse cerebral cortical astrocytes from 1 2 days newborn Kunming mice were undergone the pure culture and exposed to hypoxia. The duration of hypoxia was 3, 6, 12, 24 and 48 hours. After 24 hours hypoxia, the reoxygenation time was 0, 3, 6, 12, 24 and 48 hours. The expressions of HSP70 mRNA and HSP70 protein were detected by in situ hybridization and immunohistochemiscal methods, respectively. Results The HSP70 mRNA expression was shown by in situ hybridization 3 hours after hypoxia, and the expression of HSP70 mRNA increased with lengthening hypoxic time. The peak time of the HSP70 mRNA expression was 6 hours. There was no HSP70 mRNA expression in controls. The expression of HSP70 protein could hardly be detected after hypoxic. After the treatment of reoxygenation in astrocytes, the expression of HSP70 mRNA could be detected, and the expression of HSP70 protein could also be detected. Conclusion Although the hypoxia could induce the expression of HSP70 mRNA, the synthesis of HSP70 protein could only be observed after reoxygenation. It is possible that HSP70 might play a protective role in hypoxia/reoxygenation of astrocytes.
出处
《中华儿科杂志》
CAS
CSCD
北大核心
2000年第4期235-238,I004,共5页
Chinese Journal of Pediatrics
基金
"九五"国家医学科技攻关项目基金!资助项目 (96 90 40 6 0 4 )
