• The Korean Journal of Physiology and Pharmacology
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• v.28 no.1
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• pp.93-103
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• 2024

Satellite glial cells (SGCs), a major type of glial cell in the autonomic ganglia, closely envelop the cell body and even the synaptic regions of a single neuron with a very narrow gap. This structurally unique organization suggests that autonomic neurons and SGCs may communicate reciprocally. Glial Ca²⁺ signaling is critical for controlling neural activity. Here, for the first time we identified the machinery of store-operated Ca²⁺ entry (SOCE) which is critical for cellular Ca²⁺ homeostasis in rat sympathetic ganglia under normal and pathological states. Quantitative realtime PCR and immunostaining analyses showed that Orai1 and stromal interaction molecules 1 (STIM1) proteins are the primary components of SOCE machinery in the sympathetic ganglia. When the internal Ca²⁺ stores were depleted in the absence of extracellular Ca²⁺, the number of plasmalemmal Orai1 puncta was increased in neurons and SGCs, suggesting activation of the Ca²⁺ entry channels. Intracellular Ca²⁺ imaging revealed that SOCE was present in SGCs and neurons; however, the magnitude of SOCE was much larger in the SGCs than in the neurons. The SOCE was significantly suppressed by GSK7975A, a selective Orai1 blocker, and Pyr6, a SOCE blocker. Lipopolysaccharide (LPS) upregulated the glial fibrillary acidic protein and Toll-like receptor 4 in the sympathetic ganglia. Importantly, LPS attenuated SOCE via downregulating Orai1 and STIM1 expression. In conclusion, sympathetic SGCs functionally express the SOCE machinery, which is indispensable for intracellular Ca²⁺ signaling. The SOCE is highly susceptible to inflammation, which may affect sympathetic neuronal activity and thereby autonomic output.

• Restorative Dentistry and Endodontics
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• v.22 no.2
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• pp.782-791
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• 1997

Glial fibrillary acidic protein(GFAP) are a group of intermediate filaments that are distributed in the cytoplasm of many type of glial cells. The purpose of this study was to determine change of GFAP immunoreactivity(GFAP-IR) in rat trigeminal ganglion satellite cells in response to pulp exposure. The immunohistochemistry was carried out using the avidinbiotin-peroxidase complex(ABC) method and subsequently stained with AEC(3-aminoethyl-9-carbasol). 1. Contol group; Central root astrocytes had strong GFAP-IR, but ganglion satellite cells occasionlly had GFAP-IR. This reaction patterns of ganglion satellite cells was not concenturated in any specific region of trigeminal ganglion. 2. Three day pulp exposure group; There was a highly GFAP-IR in satellite cells of trigeminal ganglion in maxillary region. GFAP-IR in neighboring mandibular and ophthalmic regions was less intense compared to maxillary region. 3. Seven day pulp exposure group; In this group, GFAP-IR that was increased compared to control group was seen in the maxillary region. But GFAP-IR was less intense compared to three day pulp exposure group. These results suggest that GFAP in satellite cell increase in specific region of trigeminal ganglion after pulp exposure and offer useful tool in trigeminal pain research.

• Journal of the korean academy of Pediatric Dentistry
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• v.25 no.1
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• pp.249-256
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• 1998

Glial fibrillary acidic proteins (GFAP) are a group of intermediate filaments that are distributed in the cytoplasm of glial cells. GFAP immunoreactivity (GFAP-IR) increase after central and peripheral nerve injuries. The purpose of this study was to determine change of GFAP-IR in rat trigeminal ganglion satellite cells following the axotomy of inferior alveolar nerve(IAN). The immunohistochemistry was carried out using the avidin-biotin-peroxidase complex(ABC) method. 1. Control group : Astrocytes in central root of trigeminal ganglion had strong GFAP-IR, but satellite cells of trigeminal ganglion occasionally had GFAP-IR. The patterns of reactivity in satellite cells of trigeminal ganglion were not concenturated in any specific region of trigeminal ganglion. 2. Three day group after IAN axotomy : There were highly GFAP-IR in satellite cells of trigeminal ganglion in mandibular region. GFAP-IR in maxillary and ophthalmic regions were less intense compared to mandibular region. 3. Seven day group after IAN axotomy : GFAP-IR that were increased compared to control group were seen in the mandibular region. But GFAP-IR were less intense compared to three day group. These results suggest that GFAP-IR increase in specific region of trigeminal ganglion following peripheral axotomy. therefore we suppose that GFAP study offer research tool in trigeminal neuralgia.