摘要：

This review of the action of endogenous dopamine the immediate precursor of norepinephrine is confined to a brief description of the cardiovascular and renal actions of dopamine and selective summaries of clinical investigations. The agent increases myocardial contractility and heart rate by direct action on beta-adrenergic receptors. It also releases norepinephrine from myocardial catecholamine storage sites. Dopamine can cause both relaxation and contraction of vascular smooth muscle with the predominant effect depending on the vascular bed studied and dose administered. Large doses result in vasoconstriction. In addition to direct action on receptors (dopamine receptors [ beta] and alpha-adrenergic receptors) dopamine causes cardiovascular actions by reflex and neurogenic mechanisms. Hemodynamic effects of dopamine depend on the dose administered and the individual. A 1-10 mcg/kg/minute intravenous infusion leads to cardiac contractility cardiac output and renal blood flow in normal subjects. Heart rate does not change and mean arterial blood pressure is either unchanged or slightly decreased. Intravenous dopamine given to dogs in doses that increase cardiac output or contractility causes an increase in coronary blood flow. The hemodynamic effects of dopamine have not been duplicated by other sympathomimetic amines. Dopamine must be diluted before being used clinically. For most uses this means using 1 ampoule of Inotropin transferred to either a 250-ml of 500-ml bottle of an intravenous sterile solution (nonalkaline). 10 years of clinical investigation have accumulated about 1000 patients who have demonstrated the beneficial effect of dopamine in shock including cardiogenic septic and traumatic shock cases. The most serious adverse effects are ventricular arrhythmias. Possible future uses include using dopamine to increase the renal blood flow in patients with cirrhosis.

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