心の中のエピネフリン:吸収と放出,しかし,ノレピネフリン放出の促進はありません
Thomas W Lameris1, Sandra de Zeeuw, Dirk J Duncker
1Department of Internal Medicine, Cardiovascular Research Institute COEUR, Erasmus University Rotterdam, Rotterdam, The Netherlands.
Circulation
|August 15, 2002
まとめ
エピネフリンは心臓の交感性ニューロンから放出されるが,心臓におけるノレピネフリンの放出を増加させない. この研究では,心臓のノレピネフリン放出におけるエピネフリンの役割が調査されました.
科学分野:
- 心臓病学 心臓病学
- 神経科学は神経科学である.
- 薬理学 薬理学とは
背景:
- 以前の研究によると,エピネフリンは,共感神経からプレシナプス受容体経由でノレピネフリンの放出を増やす可能性があるという.
- 心臓におけるこのメカニズムの証拠は限られ,矛盾しています.
- この研究は,心臓のノレピネフリン放出におけるエピネフリンの役割を明らかにすることを目的とした.
研究 の 目的:
- 心臓の交感神経によって吸収され,放出されるエピネフリンが,心筋間位液 (NE(MIF)) のノレピネフリン濃度を上昇させるかどうかを調査する.
- この効果が基礎条件下および交感活性化中に発生するかどうかを判断する.
主な方法:
- 豚の心臓モデルで微細透析を活用した.
- エピネフリンを基礎状態で冠内注入し,左のステラートギャングリオン刺激中に注入します.
- エピネフリンの吸収と放出を評価するために投与されたチラミン.
主要な成果:
- 冠内エピネフリン注入は,インタースティシャルおよび冠動脈静脈エピネフリンレベルを有意に増加させましたが,NE (MIF) を変化させませんでした.
- 左の星状のギャングリオン刺激はNEを増加させましたが,エピネフリンの共注入は,この効果を高めませんでした.
- エピネフリンは,心臓の交感性ニューロンによって吸収と放出が示され,注入後の心筋間液エピネフリンの増加が示されています.
結論:
- この研究は,心臓の交感性ニューロンからエピネフリンが放出されることを確認した.
- エピネフリンが基礎的または活性化された条件下で心臓のシンパトネウラルノレピネフリン放出を増加させるという証拠は見つかりませんでした.
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