大鼠星型胶质细胞的IP_3-和非IP_3-敏感钙库的特征和相关性

Property of IP_3-sensitive and non-IP_3- sensitive calcium stores in rat astrocytes and their relationship

目的 研究纯化培养的大鼠星型胶质细胞的IP3 和非IP3 敏感钙库的特征和相关性。方法 用显微荧光测量技术监测单个星型胶质细胞内钙信号的动态变化 ,用IP3 敏感钙库和非IP3 敏感钙库的激活剂MCh和CAF及线粒体解偶剂FCCP刺激胶质细胞 ,观察它们胞内钙信号的影响。结果 在大部分细胞上 ,两种钙库中的任何一种被削弱或完全排空后 ,另一种钙库被激活所诱发的 [Ca2 + ] I 的升高幅度不受影响或仅被轻度抑制 ;而在少数细胞上 ,一种钙库被削弱或完全排空后 ,另一种钙库被激活所诱发的 [Ca2 + ] I 的升高幅度明显降低。结论 研究显示星型胶质细胞内的钙库包括 :IP3敏感和非IP3敏感的两种内质网钙库 。

Objective To study the property of the IP 3 sensitive and non IP 3 sensitive calcium stores in rat astrocytes and their relationship. Methods By using the microfluorescent technique, the intracellular calcium signals of the astrocytes were detected and observed dynamically. By different combination of calcium store activators (MCh, CAF) and a decoupling agent (FCCP), the astrocytes were stimulated and its effects on the intracellular calcium signals were analysed. Results In most cells, when one kind of calcium store was attenuated or exhausted, the magnitude of elevation of [Ca 2+ ] I , induced by the calcium store activator, was not significantly affected or only slightly inhibited; but in some cells, this magnitude of elevation of [Ca 2+ ] I was markedly reduced. Conclusion There are two types of calcium stores existing in the astrocytic endoplasmic reticulum, one is IP 3 sensitive and the other is non IP 3 sensitive. They have intimate or relatively independent relationship.