Cardiovascular effects of dopamine in developing swine.

ABSTRACT

Cardiac function and peripheral blood flows were measured before and during single intravenous injections of dopamine (2-25 micrograms/kg) in developing and mature swine anesthetized with pentobarbital. A positive inotropic effect was observed in even the youngest swine. Renal vasoconstriction was observed even after low doses of dopamine in animals younger than 1 month of age, and femoral vasoconstriction in animals younger than 2 weeks of age, unless alpha-adrenergic receptors were blocked by phentolamine. We concluded that the vasodilator responses to dopamine are slower to develop in the renal than in the femoral circulation.