Role of aqauaporin-4 in the aqueous humor dynamics

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K09441
• 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: Niigata University
• Principal Investigator: Ueki Satoshi 新潟大学, 脳研究所, 助教 (90595117)
• Co-Investigator(Kenkyū-buntansha): Huber Vincent 新潟大学, 脳研究所, 准教授 (40422620)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: アクアポリン4 / post-iridial flow / glymphatic flow

Outline of Final Research Achievements

The purpose of this study was to clarify the role of aquaporin-4 in post-iridial flow, the pathway of aqueous humor through the vitreous to the retina. We performed JJ vicinal coupling proton exchange magnetic resonance imaging (JJVCPE MRI), a technique to observe the signal changes induced by H2(17)O injected through the femoral vein in aquaporin -4 knockout and control mice. The signal changes in the vitreous body were significantly greater in the aquaporin-4 knockout mice group than in the control mice group. This result suggests that H2(17)O injected into the femoral vein of mice becomes as a part of aqueous humor and flows into the vitreous body, and that the inflow of water from the vitreous into the retina via aquaporin-4 in Muller cells of the retina probably be diminished in aquaporin-4 knockout mice. The inflow of water into the retina via aquaporin-4 suggested in this study indicates that the system called glymphatic flow in the brain may also exist in the retina.

Free Research Field

眼生理学

Academic Significance and Societal Importance of the Research Achievements

本研究は、網膜内にも脳内のglymphatic flowと呼ばれるシステムが存在する可能性を示した。脳内のglymphatic flowは老化に伴い有病率が増加するアルツハイマー病の病態に深く関わっているため、本研究の結果は老化に伴い有病率が増加する眼科疾患である緑内障や加齢黄斑変性の病態に網膜内のglymphatic flowが関わっている可能性をも示す。本研究は緑内障や加齢黄斑変性の病態の理解さらには治療への新たな扉を開く。