Stephenson J L, Byers M R
Department of Anesthesiology, University of Washington, Seattle 98195.
Exp Neurol. 1995 Jan;131(1):11-22. doi: 10.1016/0014-4886(95)90003-9.
Glial fibrillary acidic protein (GFAP) is a member of a heterogeneous group of intermediate filaments in glial cells of both the central and peripheral nervous systems. We demonstrate here that satellite cells in the trigeminal ganglion (TG) increase immunoreactivity (IR) for GFAP in response to dental injury. The satellite cell reaction was most often confined to the somatotopic region of the ganglion that corresponded to the zone of damage in the periphery, although in some cases it was seen to spread out from a focal center in the maxillary region to neighboring zones corresponding to cell bodies that innervate other tissues such as the cornea. We used two methods to demonstrate that the increase in satellite cell GFAP-IR was site specific and injury related. First, by altering the site of the pulp exposure from the maxillary molars to the mandibular molars, we could change the site of satellite cell reaction in the TG. Second, we used combined retrograde transport of DiI from the molar pulp and GFAP immunofluorescence to show direct correspondence between neurons that innervate the molars and neurons that are encircled by GFAP-IR satellite cells. The satellite cell GFAP-IR was seen at 3 and 7 days, the longest time point examined here. This GFAP response in satellite cells around injured sensory neurons will be a useful tool in future studies of mechanisms in trigeminal pain and neuron-support cell interactions. We conclude that a GFAP-IR satellite cell reaction is induced in TG by an injury to the molar pulp in a site specific manner at 3-7 days.
胶质纤维酸性蛋白（GFAP）是中枢神经系统和外周神经系统胶质细胞中异质性中间丝蛋白家族的成员。我们在此证明，三叉神经节（TG）中的卫星细胞会因牙齿损伤而增加GFAP的免疫反应性（IR）。卫星细胞反应最常局限于神经节的躯体定位区域，该区域与外周的损伤区域相对应，尽管在某些情况下，可观察到它从上颌区域的一个焦点中心扩散到与支配其他组织（如角膜）的细胞体相对应的相邻区域。我们使用两种方法来证明卫星细胞GFAP-IR的增加是位点特异性的且与损伤相关。第一，通过将牙髓暴露部位从上颌磨牙改变为下颌磨牙，我们可以改变TG中卫星细胞反应的部位。第二，我们使用从磨牙牙髓逆行转运DiI和GFAP免疫荧光相结合的方法，来显示支配磨牙的神经元与被GFAP-IR卫星细胞环绕的神经元之间的直接对应关系。在3天和7天时观察到卫星细胞GFAP-IR，这是此处检测的最长时间点。受损感觉神经元周围卫星细胞中的这种GFAP反应将成为未来三叉神经痛机制及神经元与支持细胞相互作用研究的有用工具。我们得出结论，在3 - 7天时，磨牙牙髓损伤以位点特异性方式在TG中诱导出GFAP-IR卫星细胞反应。
