<prompt> Dopamine is preferred in treatment of shock because of:Renal vasodilatory effectIncreased cardiac outputPeripheral vasoconstrictionProlonged action  <response>: Ans. A Renal vasodilatory effectRef: Katzung 11e p137Dopamine 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. 