A dual system of intercellular calcium signaling in glial nets associated with lanceolate sensory endings in rat vibrissae
A dual system of intercellular calcium signaling in glial nets associated with lanceolate sensory endings in rat vibrissae
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DOI：
10.1002/cne.21756
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发表时间：
2008-09-01
影响因子：
2.5
通讯作者：
Furuya, Kishio
中科院分区：
文献类型：
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作者：
Takahashi-Iwanaga, Hiromi;Nio-Kobayashi, Junko;Furuya, Kishio
披针形的感觉末梢在毛囊周围形成栅栏，与分支的许旺细胞网络相关。为了确定这些神经胶质网络作为Ca（2+）信号的可能管道的性质，通过共聚焦显微镜观察从大鼠触须分离的披针形末梢，同时通过机械刺激局部激活信号。间隙连接的细胞间耦合也进行了评估，采用荧光恢复后光漂白（FRAP）和透射电子显微镜（TEM）的技术。结果表明，神经胶质细胞Ca（2+）信号可以以两种形式在披针形神经元之间传播：快速信号来源于单个雪旺氏突，覆盖机械刺激位点周围的披针形轴突终末;延迟信号来源于刺激位点，通过初级激活细胞的胞质分支到达邻近的细胞突。前者的信号传导被抑制的抗嘌呤能药物苏拉明和腺苷三磷酸双磷酸酶，而后者是敏感的差距连接阻断剂carbenoxolon。FRAP实验和TEM观察证实了不同细胞来源的雪旺氏过程之间存在间隙连接通信。这些结果表明，在雪旺氏网络中，嘌呤能诱导的Ca（2+）信号和依赖于缝隙连接的Ca（2+）信号以各自的时空模式传播，构成机械感受器栅栏之间两种不同形式的通信。
The lanceolate sensory endings that form palisades around the hair follicle associate with networks of branched Schwann cells. To define the properties of these glial networks as possible conduits of Ca(2+) signals, lanceolate endings isolated from rat vibrissae were observed by confocal microscopy while the signaling was locally activated by mechanical stimulation. Intercellular coupling by gap junctions was also assessed by a technique employing fluorescence recovery after photobleaching (FRAP) and by transmission electron microscopy (TEM). Results showed that the glial Ca(2+) signals can spread among the arrays of lanceolates in two forms: rapid signals that originate in individual Schwann processes covering the lanceolate axon terminals around the locus of mechanical stimulation, and delayed ones that travel from the stimulation locus through cytoplasmic arborization of the primarily activated cell to the adjacent cell processes. The former signaling was suppressed by the antipurinergic agents suramin and apyrase, whereas the latter was sensitive to the gap junction blocker carbenoxolon. FRAP experiments and TEM observations corroborated the presence of gap junction communications between the Schwann processes of different cell origins. These findings show that, in the Schwann networks, purinergically induced Ca(2+) signals and those dependent on gap junctions are propagated in their own spatiotemporal patterns to constitute two distinct forms of communication among the mechanoreceptor palisades.