Division of Oral and Craniofacial Anatomy, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan; Liaison Center for Innovative Dentistry, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan.
Division of Oral and Craniofacial Anatomy, Graduate School of Dentistry, Tohoku University, Sendai 980-8575, Japan.
J Chem Neuroanat. 2019 Mar;96:116-125. doi: 10.1016/j.jchemneu.2019.01.005. Epub 2019 Jan 10.
Transient receptor potential melastatin-3 (TRPM3) is a nonselective cation channel, has permeability of Ca, and probably participates in thermosensitive nociception. In this study, immunohistochemistry for TRPM3 was conducted in the rat trigeminal, glossopharyngeal and vagal sensory ganglia. TRPM3-immunoreactivity was expressed by half of sensory neurons in the trigeminal (TG), petrosal (PG) and jugular ganglia (JG), and by about 80% of sensory neurons in the nodose ganglion (NG). They mostly had small to medium-sized cell bodies. A trichrome immunofluorescence method showed co-existence of TRPM3 with TRP vanilloid 1 (TRPV1) and calcitonin gene-related peptide (CGRP). Approximately 70% of TRPM3-immunoreactive (-IR) neurons contained TRPV1-immunoreactivity in all the examined ganglia. More than 40% of TRPM3-IR neurons exhibited CGRP-immunoreactivity in the TG, PG and JG. Only a few sensory neurons co-expressed TRPM3- and CGRP-immunoreactivity in the NG. In addition, more than 40% of TRPM3-IR neurons bound to isolectin B4 in all the examined ganglia. By combination of retrograde tracing method and immunohistochemistry, half of TG neurons innervating the facial skin and incisive papilla expressed TRPM3-immunoreactivity whereas approximately 20% of those innervating the tooth pulp contained TRPM3-immunoreactivity. Co-expression of TRPM3-immunoreactivity with TRPV1- or CGRP-immunoreactivity was common among cutaneous and papillary TG neurons but not among pulpal TG neurons. More than 60% of PG and JG neurons innervating the external ear canal skin and circumvallate papilla contained TRPM3-immunoreactivity. Co-expression of TRPM3 with TRPV1 or CGRP was common among PG and JG neurons innervating the external ear canal skin. However, a smaller number of TRPM3-IR neurons co-expressing TRPV1- or CGRP-immunoreactivity innervate the circumvallate papilla in the PG. The present study suggests that expression of TRPM3 and its co-existence with TRPV1 and CGRP in sensory neurons depend on the variety of their peripheral targets in the trigeminal, glossopharyngeal and vagal nervous systems.
瞬时受体电位 melastatin-3（TRPM3）是一种非选择性阳离子通道，对 Ca 具有通透性，可能参与热敏性伤害感受。在这项研究中，我们对大鼠三叉神经、舌咽神经和迷走神经感觉神经节中的 TRPM3 进行了免疫组织化学染色。TRPM3 免疫反应性存在于三叉神经节（TG）、岩神经节（PG）和颈静脉神经节（JG）中的一半感觉神经元中，也存在于结神经节（NG）中的约 80%感觉神经元中。它们的胞体大多为中小型。三色免疫荧光法显示 TRPM3 与 TRPV1 和降钙素基因相关肽（CGRP）共存。在所有检查的神经节中，约 70%的 TRPM3 免疫反应性（-IR）神经元含有 TRPV1 免疫反应性。在 TG、PG 和 JG 中，超过 40%的 TRPM3-IR 神经元表达 CGRP 免疫反应性。在 NG 中，只有少数感觉神经元同时表达 TRPM3 和 CGRP 免疫反应性。此外，在所有检查的神经节中，超过 40%的 TRPM3-IR 神经元与异硫氰酸荧光素 B4 结合。通过逆行示踪法和免疫组织化学相结合的方法，支配面部皮肤和切牙乳头的 TG 神经元中有一半表达 TRPM3 免疫反应性，而支配牙髓的 TG 神经元中约有 20%表达 TRPM3 免疫反应性。在支配皮肤和乳突 TG 神经元中，TRPM3 免疫反应性与 TRPV1 或 CGRP 免疫反应性的共表达很常见，但在支配牙髓 TG 神经元中则不然。支配外耳道皮肤和环甲乳头的 PG 和 JG 神经元中有超过 60%表达 TRPM3 免疫反应性。在支配外耳道皮肤的 PG 和 JG 神经元中，TRPM3 与 TRPV1 或 CGRP 共表达很常见。然而，在 PG 中，支配环甲乳头的 TRPM3-IR 神经元中，表达 TRPV1 或 CGRP 免疫反应性的神经元数量较少。本研究表明，TRPM3 的表达及其与 TRPV1 和 CGRP 的共存取决于三叉神经、舌咽神经和迷走神经感觉神经系统中感觉神经元外周靶标的多样性。
