Morphology & Physiology of Solitary Chemoreceptor Cells

形态学

• 批准号: 7114575
• 负责人: Brian D Gulbransen
• 金额: $ 2.72万
• 依托单位: UNIVERSITY OF COLORADO DENVER
• 依托单位国家: 美国
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-03-20 至 2007-09-19
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7114575
• 关键词: chemoreceptors; fingers; glutamate receptor; immunocytochemistry; innervation; ligands; morphology; neuropeptides; nociceptors; physiology; receptor; taste; trigeminal nerve

DESCRIPTION (provided by applicant): Nasal trigeminal chemosensitivity in mice and rats is mediated in part by solitary chemoreceptor cells (SCCs) in the nasal epithelium. SCCs express the G-protein a-gustducin in addition to other elements of the "bitter"- taste signaling cascade including PLCp2, TrpM5 and T2R "bitter"-taste receptors. Many noxious substances elicit the sensation of bitter taste in the oral cavity but are irritating or painful in the nasal cavity. The proposed experiments fall into 2 aims: first to describe what type of trigeminal nociceptive fibers innervate SCCs. We will utilize immunocytochemistry to assay nerve fibers innervating SCCs for neuropeptide content, the ability to bind isolectin B4, and the expression of P2X3 and kainate receptors, both of which are commonly expressed by nociceptive fibers. Second, we will investigate which part of the SCC response is TrpM5-mediated. TrpMS is an obligatory component of T2R-mediated responses in taste cells and TrpM5- KO mice lack taste responses to T2R ligands. We will use calcium imaging to visualize SCC responses to test stimuli from a panel of classic bitter and trigeminal stimuli. Responses will be recorded in SCCs from both wild type and TrpM5-KO mice to separate TrpM5 and non-TrpM5-mediated responses.

描述（由申请人提供）：小鼠和大鼠的鼻三叉神经化学敏感性部分由鼻上皮中的孤立化学感受器细胞（SCC）介导。 SCC 表达 G 蛋白 a-gustducin，此外还表达“苦味”信号级联的其他元件，包括 PLCp2、TrpM5 和 T2R“苦味”味觉受体。许多有毒物质会在口腔中引起苦味，但在鼻腔中会产生刺激或疼痛。拟议的实验分为两个目标：首先描述什么类型的三叉神经伤害性纤维支配 SCC。我们将利用免疫细胞化学来测定支配 SCC 的神经纤维的神经肽含量、结合异凝集素 B4 的能力以及 P2X3 和红藻氨酸受体的表达，这两种受体通常由伤害性纤维表达。其次，我们将研究 SCC 反应的哪一部分是 TrpM5 介导的。 TrpMS 是味觉细胞中 T2R 介导的反应的必要组成部分，TrpM5-KO 小鼠缺乏对 T2R 配体的味觉反应。我们将使用钙成像来可视化 SCC 对一组经典苦味和三叉神经刺激的测试刺激的反应。将记录野生型和 TrpM5-KO 小鼠的 SCC 中的反应，以区分 TrpM5 和非 TrpM5 介导的反应。