地塞米松诱导培养的大鼠大脑皮质星形胶质细胞凋亡

目的　研究地塞米松诱导纯化培养的大鼠大脑皮质星形胶质细胞凋亡的作用。方法　不同浓度的地塞米松(浓度为 10 -3 、 10 -4、 10 -5mol/L)与纯化培养的大鼠大脑皮质星形胶质细胞共同孵育 18小时后 ,吖啶橙染色荧光显微镜观察细胞凋亡形态学改变 ,流式细胞仪检测细胞凋亡和结晶紫比色法酶标仪测定活细胞数。结果　 (1)吖啶橙染色荧光显微镜观察 :10 -4组偶见细胞凋亡 ,10 -3 组可见许多细胞有典型的凋亡形态学改变核固缩 ,深染 ,或肿胀 ,碎裂 ,并可见凋亡小体。 (2 )流式细胞仪检测细胞凋亡 :10 -3 组细胞凋亡率为 15 99% ,与其它三组相比明显增高 ,有显著性差异 (P <0 0 1)。 (3)结晶紫法酶标仪测定活细胞数 :10 -3 组OD值为 0 . 185与其它三组相比明显下降 ,有显著性差异 (P <0 0 1) ,表明活细胞数明显减少。结论　大剂量地塞米松可诱导体外的星形胶质细胞凋亡。

APOPTOSIS OF ASTROCYTES INDUCED BY DEXAMETHASONE

Objective To study the effects of dexamethasone on the apoptosis of pure clutured astrocytes from newborn rat cerebral cortex. Method Pure astrocytes were co cultured with dexamethasone of different concetrations for 18 hours. The apoptotic morphologic changes were observed by fluorescent microscopy with acridinne orange staining, the apoptotic cells heve examined though flow cytometry, and the activity of cells was determined crystal violet dye. Result (1) Morphologic observation showed that man cells in the 10 -3 group underwent karyopyknosis, condensation, swelling or splitting and apoptotic bodies were obserered. In the 10 -4 group, very few apoptotic cells were observed. (2) Flow cytometry showed that dexamethasone of 10 -3 concentration can induce significantly more astrocyte apoptosis than in the other groups, the apoptotic rate being 15 99% ( P <0 01). (3) The cell number in the 10 -3 group decreased apparently In all the above 3 saspects, no great changes were found 10 -4 group, 10 -5 group and control group ( P >0 05). Conclusion Dexamethasone might induce astrocyte apoptosis in vitro.