IM: To
study the effects of
dopexamine hydrochloride (Dop) on heart
functions and coronary flow (CF) of normal
and hypoxic isolated
perfusing heart and compare the effects of Dop with those of
fenoldopam hydrochloride (Fen) and
procaterol hydrochloride (Pro).
METHODS: The isolated rabbit normal and hypoxic hearts were perfused
with Krebs Henseleit (K H) solution via aorta at 37±0 5 ℃. The
drug were added into the K H solution. RESULTS: Dop
increased the
CF, left ventricular contractile function ( +d p / d t max
etc) and heart rate (HR) in normal heart; Fen increased the heart
function more potently, but increased the CF to a lesser degree than
Dop did, whereas the effects of Pro was the least. In simple hypoxic
group, at 30 min of perfusion, the +d p /d t max and CF
decreased by 66±4 % and 48 1±1 0 %, respectively. Dop remarkably
attenuated the decreases in both CF and heart function during hypoxia
as it decreased the +d p /d t max by 32 0±2 4 % and CF
by 28±3 %. Fen was less potent than Dop in attenuating the
diminution of CF, while Pro was the least effective. CONCLUSION: Dop
has a better prospect in the treatment of ischemic heart disease in
view of its dual action of increasing CF and inotropism.