臨床検査57巻6号

2013年06月発行

今月の特集1 尿バイオマーカー

尿中アクアポリン2の病態検査上の意義

著者： 佐々木成¹

所属機関： ¹東京医科歯科大学大学院腎臓内科学

ページ範囲：P.637 - P.641

■アクアポリン2（AQP2）はバソプレシン反応性の水チャネルで，腎臓集合管に存在し尿濃縮に必須の役割を果たしている．

■尿中にエクソソームとして排泄され，免疫ブロット法，RIA法，ELISA法で測定が可能であり，バソプレシン作用の指標になると考えられている．

■臨床症例での測定において，尿中AQP2排泄量は尿濃縮力の低下する疾患（中枢性ならびに腎性尿崩症）で減少し，一方尿濃縮力が亢進し尿希釈不全となる疾患（心不全，肝硬変，SIADH）で増加することが示されている．

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