Dopamine is preferred in treatment of shock because of:
Renal vasodilatory effect
Increased cardiac output
Peripheral vasoconstriction
Prolonged action
Ans. (A) Renal vasodilatory effect(Ref: Katzung 11/e p137)Dopamine acts on D1 , b1 and a1 receptors. Stimulation of D1 receptors cause renal vasodilation, which is useful clinically to improve renal perfusion in shock with oligouria.
Adrenergic System