ドカルパミンの心力学的作用に与える低酸素状態の影響—実験的検討

Influence of Hypoxia on Hemodynamic Effect of Docarpamine:An experimental study

　実験的に低酸素状態を作製し，ドパミン（DOA）prodrugであるドカルパミン（DCP）が，低酸素状態下でいかなる効果を発揮するか，デノパミン（DNOP）と対比して検討した．その結果，以下のことが示された．1） DCPの陽性変力作用は低酸素状態下においては有意に発現しないが，末梢血管拡張作用は正酸素状態下と同様維持される．2） DNOPは低酸素状態下でも明らかな陽性変力作用と同時に有意の陽性変時作用を示し，また軽度ながら血管拡張作用も認めた．3） DCP,DNOPは基本的薬理学的性質として類似した薬効を持つが，低酸素状態下ではその作用を異にする．すなわち，低酸素状態下においてDCPの陽性変力作用はアシドーシスの影響を受けるものの，その血管拡張作用と相まって心拍数に影響を与えることなく，心拍出量を維持し得る薬剤である．

The influence of hypoxia on hemodynamic effect of docarpamine (DCP) was compared with that of denopamine (DNOP), experimentally.

Results obtained from these experiments were as follows; 1) Although the positive inotropic action of DCP did not appear significantly in hypoxia, the vasodilating effect was maintained as well as in normoxia.

2) DNOP produced both an apparent positive inotropic action and a significant positive chronotropic action even in hypoxia, and also revealed slight vasodilating effect.

3) Although DCP had similar effects to DNOP on basic pharmacological characteristics, there were different effects between two drugs in hypoxia. Namely, despite the affection of the inotropic action of DCP by the acidosis, it maintained cardiac output without increase of heart rate combined with its vasodilating effect.