Novel regulatory mechanisms of corneal nerves by acetylcholine in the detection of ocular dryness

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K09814
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 56060:Ophthalmology-related
• Research Institution: Kanazawa Medical University
• Principal Investigator: MASUOKA Takayoshi 金沢医科大学, 医学部, 教授 (80509307)
• Co-Investigator(Kenkyū-buntansha): 橋川 成美 (芳原成美) 岡山理科大学, 理学部, 准教授 (30511159)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 角膜神経 / アセチルコリン / ニコチン受容体 / ドライアイ

Outline of Final Research Achievements

In this study, the regulatory system of corneal sensory nerves by endogenous acetylcholine and its relevance to dry eye were examined using guinea pigs. We found that the excitation of corneal sensory nerves, especially cold-sensitive ones, is controlled by nicotinic acetylcholine receptors containing alpha 4 subunits. Endogenous acetylcholine in the cornea is mainly synthesized and released by epithelial cells located in the basal portion of epithelium. The excitation of corneal nerves and blinking induced by stimulation of nicotinic receptor are changed in dry eye model guinea pigs.

Free Research Field

眼薬理学

Academic Significance and Societal Importance of the Research Achievements

本研究により、角膜におけるアセチルコリンを介した感覚神経の制御機構の一端を明らかにすることができた。また、角膜神経を調節するα4ニコチン性アセチルコリン受容体が、ドライアイの自覚症状を改善する治療薬の標的のひとつになり得ることを示すことができた。