内生的なNa,Kポンプリガンドは,ダールラットの急性NaCl負荷の間に異なる調節されます
O V Fedorova1, E G Lakatta, A Y Bagrov
1Laboratory of Cardiovascular Science, Intramural Research Program, National Institute on Aging, Baltimore, MD 21224, USA.
Circulation
|January 11, 2000
まとめ
急性塩負荷は,ダール塩敏感性 (DS) のラットにおいてマリノブファゲニン (MBG) を増加させ,ナトリウム分泌の低下を補償することを示唆する. オアバイン類化合物 (OLC) のレベルは一時的に上昇します.
科学分野:
- 生理学 生理学とは
- エンドクリノロジー エンドクリノロジー
- 腎臓科学 腎臓科学とは
背景:
- 2つの内生的なデジタリスのような因子,オアバインのような化合物 (OLC) とマリノブファゲーニン (MBG) は,特定のNa(+),K(+) -ATPaseイソフォームを標的とする.
- OLCはα-3を標的とし,MBGはα-1 Na(+),K(+) -ATPaseを標的とする.
研究 の 目的:
- 急性塩化ナトリウム (NaCl) 負荷によるMBGとOLCの調節をダール塩感受性 (DS) と塩耐性 (DR) のラットで比較する.
- NaCl負荷に対するナトリウレット反応におけるMBGとOLCの役割を調査する.
主な方法:
- 成人した雄性DSとDRネズミは,腹膜内NaCl負荷を受けた.
- MBGとOLCの尿路,ナトリウレシス,腎臓分泌,組織レベルを測定した.
- DS,DR,およびWistarラットにおけるMBGとオアバインによる腎臓のNa(+),K(+) -ATPaseの抑制を比較した.
主要な成果:
- DSラットは,より高い血ナトリウムにもかかわらず,DRラットと比較して,NaCl負荷に対する鈍化したナトリウレット反応を示しました.
- DSとDRの両方のラットは,OLCの一時的な増加を示したが,MBGの持続的な上昇を示した.
- MBGの排泄は,NaClの負荷を受けた後のDSラットではDRラットよりも著しく高かった.
- DSラットの腎臓Na(+),K(+) -ATPase (α-1同型) は,オアバインよりもMBGに対してより高い感受性を示した.
結論:
- DSラットの急性NaCl負荷は,一時的なOLC増加と対照的に,MBGレベルと排泄の持続的な増加につながります.
- この発見は,DSラットにおけるMBGの生産量の上昇が,遺伝的に障害のあるプレッシャー・ナトリュレス症候群の補償メカニズムとして役立つ可能性があることを示唆している.
- DSラットのアルファ-1Na(+),K(+) -ATPaseイソフォームに対するMBGのより大きな阻害作用は,ナトリウムバランスを調節する役割をサポートします.
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