基本的酸化窒素合成は,エッセンシャル高血圧において必要である
Lancet (London, England)
|March 22, 1997
まとめ
窒素酸化物 (NO) の生成は,本質的な高血圧の患者で低い. この研究では,高血圧患者のNO合成を評価するために,NOの最終産物である窒素を測定しました.
科学分野:
- 心血管科学の研究について
- エンドクリノロジー エンドクリノロジー
- メタボリック研究
背景:
- エッセンシャル高血圧は,血管内皮における酸化窒素 (NO) 合成の変化と関連しています.
- 高血圧のNO生成を直接測定することは困難です.
- NO酸化の最終産物である窒素酸は,NO合成のバイオマーカーとして機能します.
研究 の 目的:
- 治療されていない精性高血圧の患者の酸化窒素 (NO) 産生を直接推定する.
- NO生産の指標として無機窒素合成を測定する.
- 血圧とNO合成の関係を調査する.
主な方法:
- 高血圧患者と健康な対照群を対象に2つの研究が行われました.
- 研究1 食事による窒素摂取量,尿/血の窒素量測定,24時間通行式血圧モニタリング.
- 試験2:静脈L[15N]2アルギニンの投与,24時間の循環器血圧モニタリング,および15N-ニートレートの測定のための36時間の尿採取.
主要な成果:
- 高血圧患者は,研究1 (p <0.001) の対照群と比較して,尿経24時間の窒素分泌量が有意に低かった.
- 日中の血圧と窒素分泌の間で有意な逆相関が観察されました (p = 0.007).
- 高血圧患者は,小便による36時間の15N-ニートレートの排泄量が低い (p < 0.001) と,研究2では血圧と逆相関 (p = 0.002) を示した.
結論:
- 基礎条件下における本質的な高血圧の患者では,全身の酸化窒素 (NO) の生成が減少しているように見える.
- 測定されたNOの正確な起源は不明である.
- NO合成の障害が血圧上昇の主な原因なのか,それともその結果なのかは不明である.
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