イワタ　シュウスケ   IWATA SHUSUKE   岩田　周介    所属   朝日大学  歯学部 口腔機能修復学講座 口腔生理学    朝日大学  大学院 歯学研究科    職種   講師
発表年月日	2026/09/05
発表テーマ	ENaC-Dependent Taste Responses but Limited Behavioral Impact on Sodium Ascorbate Intake in ODS Rats
会議名	歯科基礎医学会第68回学術大会
学会区分	全国学会
発表形式	ポスター
単独共同区分	共同
開催期間	2026/09/05～2026/09/06
発表者・共同発表者	安尾敏明、高橋慎平、岩田周介、硲哲崇
概要	Osteogenic disorder Shionogi/ShiJcl-od/od (ODS) rats cannot synthesize ascorbic acid (AsA). We investigated the contribution of epithelial Na⁺ channels (ENaC) to taste responses and long-term intake of sodium ascorbate (AsA-Na) in AsA-replete ODS rats using the ENaC inhibitor amiloride (Ami). Chorda tympani nerve responses to 100 mM NaCl and AsA-Na were reduced by approximately 45% and 90%, respectively, by 30 µM Ami, indicating a strong ENaC contribution to AsA-Na taste transduction. In 48-h two-bottle choice tests, Ami significantly reduced preference and intake for NaCl, whereas responses to AsA-Na were minimally affected, with preference remaining low (~20%). Ami also reduced urine volume during NaCl intake but had limited effects during AsA-Na intake. These results suggest that, despite strong ENaC involvement in peripheral AsA-Na taste responses, its long-term intake is largely independent of ENaC-mediated sodium taste and may be regulated by post-ingestive mechanisms.