意識のある犬の全身および冠動脈床に物質Pの異なった作用

Y Nakamura¹, R Parent, M Lavallée

¹Department of Physiology, Faculty of Medicine, University of Montreal Canada.

Circulation

|July 1, 1991

まとめ

物質Pは全身の血管拡張を引き起こすが,皮肉にも意識のある犬の冠動脈を収縮させる. このペプチドは,

科学分野:

心血管生理学心血管の生理学
薬理学薬理学とは

背景:

以前の研究では,物質P (SP) が麻酔を受けた動物の血管拡張剤であることを示唆していました.
SPによる冠動脈血管拡張は一時的であり,おそらくタキフィラキシーによるものである.

研究の目的:

静脈注入物質Pが全身循環と冠動脈循環に及ぼす安定状態効果を調査する.
意識のある,器具付きの犬にSPの影響を決定する.

主な方法:

無傷な自律的反射を持つ意識のある犬に静脈内投与された物質P (5ng/kg/min).
自律的影響を評価するために,ギャングリオンブロックを使用した.
直接の冠動脈効果のために,物質P (0.4ng/kg/min) の冠動脈内注入を行った.

主要な成果:

静脈内SPは心電量と心拍数を増加させ,平均動脈圧と全周回路抵抗を低下させました.
SPは冠動脈静脈収縮を引き起こし,冠動脈の血流と心筋の酸素供給を低下させた.
ギャングリオンの封鎖は,SP誘発の冠動脈収縮を悪化させた.
内冠性SPは,持続的な冠動脈血管収縮を直接引き起こしました.

結論:

意識のある犬の場合,物質Pは主に全身的血管拡張を引き起こします.
皮肉なことに,物質Pは冠動脈血管収縮を引き起こし,心筋の酸素供給を減少させます.

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