甲基强的松龙对伽玛刀照射后胶质细胞Cx43和GFAP表达的影响

目的 研究甲基强的松龙（MP）对伽玛刀照射后胶质细胞缝隙连接蛋白43（Cx43）和胶质纤维酸蛋白（GFAP）表达的影响。方法体外培养原代星形胶质细胞，经伽玛刀照射（边缘剂量32Gy）并培养36h后随机分为1μg／ml、5μg／ml、10μg／ml、20μg／ml、30μg／ml、40μg/ml组及实验对照组，各组进一步随机分为48h、72h、96h、120h4个亚组。将各组胶质细胞与相应剂量MP共培养，于48、72、96、120h各时间点采用免疫组化方法检测GFAP及Cx43的表达。结果伽玛刀照射后，胶质细胞Cx43表达降低，GFAp表达增高。添加MP后，20μg／ml、30μg／ml组Cx43呈时间依赖性上调；GFAP表达虽呈时间依赖性上升，但其峰值低于实验对照组，峰值出现时间亦晚于实验对照组。结论MP可上凋伽玛刀照射后胶质细胞Cx43的表达，抑制GFAP表达的上升趋势。

The effects of methylprednisolone on expressions of connexin 43 and GFAP in cultured rat astrocytes after irradiation by gamma knife

Objective To study the effects of methylprednisolone （MP） on expressions of connexin 43 （Cx43） and GFAP in cultured rat astroeytes after irradiation by gamma knife. Methods Rat astrocytes were cultured and irradiated by gamma knife at single dose of 32 Gy. After 36-h culture, different doses of MP were administered to the astrocytes, then the cells were divided into 1μg/ml, 5μg/ml, 10μg/ml, 20μg/ml, 30μg/ml, 40μg/ml groups and control group. Each group was further divided into four subgroups by different treated time lengths （48, 72, 96, and 120 h）. Cx43 and GFAP were observed by immunohistochemical technique at different time points （48 h, 72 h, 96 h, 120 h）. Results Compared with the control group, less Cx43 and more GFAP expressions were found in the gamma knife irradiation group. MP-induced the expression of Cx43 up-regulated in a time-dependent manner in 20μg/ml and 30μg/ml groups. GFAP was increased in a time-dependent manner, but its peak value was lower and later than the control group. Conclusion MP could increase the expression of Cx43 and inhibit the increasing tendency of GFAP expression after gamma knife treatment.