Institut für Anatomie I, Universität Erlangen-Nürnberg, 91054 Erlangen, Germany.
Histochem Cell Biol. 2010 Aug;134(2):145-57. doi: 10.1007/s00418-010-0723-9. Epub 2010 Jul 7.
Intrinsic choroidal neurons (ICNs) exist in some primates and bird species. They may act on both vascular and non-vascular smooth muscle cells, potentially influencing choroidal blood flow. Here, we report on the chemical coding of ICNs and eye-related cranial ganglia in the chicken, an important model in myopia research, and further to determine synaptic input onto ICN. Chicken choroid, ciliary, superior cervical, pterygopalatine, and trigeminal ganglia were prepared for double or triple immunohistochemistry of calcitonin gene-related peptide (CGRP), choline acetyltransferase (ChAT), dopamine-beta-hydroxylase, galanin (GAL), neuronal nitric oxide synthase (nNOS), somatostatin (SOM), tyrosine hydroxylase (TH), vasoactive intestinal polypeptide (VIP), vesicular monoamine-transporter 2 (VMAT2), and alpha-smooth muscle actin. For documentation, light, fluorescence, and confocal laser scanning microscopy were used. Chicken ICNs express nNOS/VIP/GAL and do not express ChAT and SOM. ICNs are approached by TH/VMAT2-, CGRP-, and ChAT-positive nerve fibers. About 50% of the pterygopalatine ganglion neurons and about 9% of the superior cervical ganglion neurons share the same chemical code as ICN. SOM-positive neurons in the ciliary ganglion are GAL/NOS negative. CGRP-positive neurons in the trigeminal ganglion lack GAL/SOM. The neurochemical phenotype and synaptic input of ICNs in chicken resemble that of other bird and primate species. Because ICNs lack cholinergic markers, they cannot be readily incorporated into current concepts of the autonomic nervous system. The data obtained provide the basis for the interpretation of future functional experiments to clarify the role of these cells in achieving ocular homeostasis.
固有脉络膜神经元(ICN)存在于一些灵长类动物和鸟类中。它们可能作用于血管和非血管平滑肌细胞,潜在地影响脉络膜血流。在这里,我们报告了鸡的 ICN 和与眼相关的颅神经节的化学编码,鸡是近视研究的重要模型,并进一步确定了 ICN 的突触输入。鸡脉络膜、睫状、颈上、翼腭和三叉神经节准备进行降钙素基因相关肽(CGRP)、胆碱乙酰转移酶(ChAT)、多巴胺-β-羟化酶、甘丙肽(GAL)、神经元型一氧化氮合酶(nNOS)、生长抑素(SOM)、酪氨酸羟化酶(TH)、血管活性肠肽(VIP)、囊泡单胺转运体 2(VMAT2)和α-平滑肌肌动蛋白的双重或三重免疫组织化学染色。为了记录,使用了光、荧光和共聚焦激光扫描显微镜。鸡的 ICN 表达 nNOS/VIP/GAL,不表达 ChAT 和 SOM。TH/VMAT2-、CGRP-和 ChAT-阳性神经纤维接近 ICN。大约 50%的翼腭神经节神经元和约 9%的颈上神经节神经元与 ICN 具有相同的化学编码。睫状神经节中的 SOM 阳性神经元为 GAL/NOS 阴性。三叉神经节中的 CGRP 阳性神经元缺乏 GAL/SOM。鸡 ICN 的神经化学表型和突触输入类似于其他鸟类和灵长类动物。由于 ICN 缺乏胆碱能标志物,因此它们不能轻易地被纳入当前自主神经系统的概念中。获得的数据为解释未来的功能实验提供了基础,以阐明这些细胞在实现眼球内稳态中的作用。