马桑内酯激活的星形胶质细胞条件培养液对正常大鼠脑内孕激素及其受体的影响

目的探讨星形胶质细胞对大鼠脑内孕激素及其受体的影响以及在癫痫发病中的作用。方法将马桑内酯(Coriaria lactone,CL)激活的星形胶质细胞条件培养液(Astrocytic conditioned medium,ACM)注射入正常SD大鼠侧脑室后,观察大鼠的行为变化;运用免疫组织化学方法观察大脑皮质及海马中孕激素受体(PR)表达的变化;运用放射免疫分析方法,观察脑组织匀浆及脑脊液内孕酮含量的变化。结果ACM组大鼠在注射ACM后30min出现癫痫行为,2h恢复正常;免疫组织化学显示:ACM作用后2h,PR免疫反应阳性神经元数和平均光密度值明显降低,4h达最低(P<0.05),12h恢复正常水平;放射免疫分析方法显示ACM组大鼠在侧脑室注射ACM后2h,脑脊液中孕酮含量明显升高;而海马组织和大脑皮质中孕酮含量则在注药后4h明显降低,与对照组比较均有显著差异(P<0.05)。结论以上实验结果提示马桑内酯激活的星形胶质细胞条件培养液可通过降低大鼠脑内孕激素及其受体的表达参与癫痫的反复发作。

EFFECT OF CL-ACTIVITED ASTROCYTIC CONDITIONED MEDIUM ON INTRACEREBRAL PROGESTERONE AND PROGESTERONE RECEPTORS OF NORMAL RATS

Objective To explore the effect of astrocytes on the intracerebral progesterone and its receptor,and their role in epileptogenesis.Methods The CL-activated astrocytic conditioned medium(ACM) was injected into the lateral ventricle of SD rats.Behavioural changes were observed.Immunohistochemical SPmethod wasused to observethe changes in the expression of PR in the cerebral cortex and hippocampus.The amount of progesterone wasassessed by means of radioimmunoassayin the homogenate of cerebral cortex and hippocampus and the cerebrospinal fluid.Results Seizure was observed in the ACM group 30 min after the injection of ACM,and returned to normal in 2h.According to immunohistochemistry,the immunoreaction of PR in hippocampus and cerebral cortex of experimental rats was weaker than that of the control group4h after injection and returned to normal in 12h(P<0.05).Radioimmunoassay showed that the content of progesterone markedly increased in CSF of the ACM group 2h after injection,but decreased in hippocampus and cerebral cortex 4h after injection,with significant difference to the control group(P<0.05).Conclusion The results mentioned above indicatethatthe ACM activatedby CL can decrease the expression of progesterone and PR,resulting in the recurrent attacksof epilepsy.