Revista portuguesa de cardiologia : orgão oficial da Sociedade Portuguesa de Cardiologia = Portuguese journal of cardiology : an official journal of the Portuguese Society of Cardiology
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Significant advances are emerging in what concerns the newer inotropic agents. Despite the ideal agent, whose sole action is to increase the sensitivity of contractile proteins to calcium is yet to be found, the identification of specific receptors of dopamine in the CNS and peripheral circulation, had stimulated the pharmacological research of dopaminergic receptors agonists, selective for the subtypes DA1 and DA2, selective DA1 and DA2 antagonists and the dopamine beta-hidroxilase inhibitors and represent an unequivocal value. Beta-adrenergic agonists have been extensively evaluated as positive inotropic agents in the patients with congestive heart failure. ⋯ An attenuation of these benefits may be observed at times, although new tachyphylaxis very rarely occurs. Since dobutamine does not preferentially dilate the renal vasculature, concomitant administration of dopamine, at a dose which only stimulates the dopaminergic receptors in the renal artery, had the advantage of increasing renal perfusion and improving renal function. Administration of dopamine is often prolonged after that of dobutamine, and may help the wearing off of dobutamine.(ABSTRACT TRUNCATED AT 400 WORDS)