前腕のイシュケミアの後の細胞外カルシウムと血管反応

Virginia A Imadojemu¹, Kenneth Mooney, Cindy Hogeman

¹Division of Pulmonary, Allergy, and Critical Care, The Pennsylvania State University College of Medicine, The Milton S. Hershey Medical Center, Hershey, Pa 17033, USA.

Circulation

|June 24, 2004

まとめ

細胞外カルシウムレベルの変化は,ヒトの肌性反応に大きな影響を与えます. トランスムラル圧の上昇は,カルシウムを上昇させ,その結果,四肢の血流速度を低下させます.

科学分野:

心血管生理学心血管の生理学
血管生物学血管生物学

背景:

ミオゲン反応は,圧力変化に反応して血管の直径を調節する.
メカニズムは,滑らかな筋肉細胞の脱極化とカルシウム流入を含む.
細胞外カルシウムのミオゲン反応における役割は,in vitroでは十分に確立されています.

研究の目的:

細胞外カルシウム濃度の生理学的変化が,意識のある人間における肌性反応を決定するという仮説を検証する.

主な方法:

静脈血のイオン化されたカルシウムを,インタースティシャルカルシウムの指数として測定した.
前腕の血圧と血流速度を判定した.
血圧,カルシウム濃度,血流速度との関係を分析した.

主要な成果:

血清カルシウム濃度の変化率は,トランムラ圧 (r=0.96) と強く相関していた.
カルシウム濃度は前腕の血流速度 (r=0.99) に反比例していた.

結論:

筋肉のストレッチは,トランスムラルの圧力の増加によって,未知のメカニズムを通じて,おそらく,インタースティシャルカルシウムを上昇させます.
このカルシウムの増加は,四肢の血流速度を低下させると仮定されています.

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