Distribution of transient receptor potential channels in the rat carotid chemosensory pathway
Distribution of transient receptor potential channels in the rat carotid chemosensory pathway
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DOI：
10.1002/cne.10798
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发表时间：
2003-09-22
影响因子：
2.5
通讯作者：
Kunze, DL
中科院分区：
文献类型：
--
作者：
Buniel, MCF;Schilling, WP;Kunze, DL
颈动脉体中的血管球细胞对血液的氧张力的降低做出反应，并将颈动脉窦神经中的这种感觉信息经由岩神经节中的神经元传递到大脑。与磷脂酶C相连的G蛋白偶联膜受体可能通过激活瞬时受体电位（TRP）蛋白形成的阳离子通道在这种反应中发挥重要作用。本研究采用免疫组织化学技术检测了大鼠颈动脉体和岩神经节中TRPC蛋白的表达。TRPC 3、TRPC 4、TRPC 5、TRPC 6和TRPC 7存在于整个神经节的神经元中。TRPC 1仅在28%的岩神经元中表达，在这一人群中，45%为酪氨酸羟化酶（TH）阳性，占神经节中基本上所有TH表达神经元。由于TH阳性神经元投射到颈动脉体，该结果表明TRPC 1选择性地与化学感受通路相关。通过颈动脉体的共聚焦图像显示，TRPC 1/3/4/5/6蛋白定位于颈动脉窦神经纤维，其中一些是免疫反应的抗神经丝（NF）抗体鸡尾酒。TRPC 1和TRPC 3存在于NF阳性和NF阴性纤维中，而TRPC 4、TRPC 5和TRPC 6的表达主要定位于NF阴性纤维。只有TRPC 1和TRPC 4位于传入神经末梢，包围个别球细胞。TRPC 7在感觉纤维中不表达。研究的所有TRPC蛋白都存在于I型血管球细胞中。虽然它们作为受体激活的阳离子通道在化学感受途径中的作用尚未建立，但TRPC通道在颈动脉体的血管球细胞和感觉神经中的存在表明其在促进和/或维持缺氧反应中的作用。神经学比较杂志(C)2003 Wiley-Liss，Inc.
Glomus cells in the carotid body respond to decreases in oxygen tension of the blood and transmit this sensory information in the carotid sinus nerve to the brain via neurons in the petrosal ganglion. G-protein-coupled membrane receptors linked to phospholipase C may play an important role in this response through the activation of the cation channels formed by the transient receptor potential (TRP) proteins. In the present study, expression of TRPC proteins in the rat carotid body and petrosal ganglion was examined using immunohistochemical techniques. TRPC3, TRPC4, TRPC5, TRPC6, and TRPC7 were present in neurons throughout the ganglion. TRPC1 was expressed in only 28% of petrosal neurons, and of this population, 45% were tyrosine hydroxylase (TH)-positive, accounting for essentially all the TH-expressing neurons in the ganglion. Because TH-positive neurons project to the carotid body, this result suggests that TRPC1 is selectively associated with the chemosensory pathway. Confocal images through the carotid body showed that TRPC1/3/4/5/6 proteins localize to the carotid sinus nerve fibers, some of which were immunoreactive to an anti-neurofilament (NF) antibody cocktail. TRPC1 and TRPC3 were present in both NF-positive and NF-negative fibers, whereas TPRC4, TRPC5, and TRPC6 expression was primarily localized to NF-negative fibers. Only TRPC1 and TRPC4 were localized in the afferent nerve terminals that encircle individual glomus cells. TRPC7 was not expressed in sensory fibers. All the TRPC proteins studied were present in type I glomus cells. Although their role as receptor-activated cation channels in the chemosensory pathway is yet to be established, the presence of TRPC channels in glomus cells and sensory nerves of the carotid body suggests a role in facilitating and/or sustaining the hypoxic response. J. Comp. Neurol. (C) 2003 Wiley-Liss, Inc.