<prompt> Dobutamine causes -Increased cardiac outputMarked increase in hea rateIncreased total peripheral resistanceMarked increase in BP  <response>: Ans. is a i.e., Increased cardiac output o Only prominent action of dobutamine is in increase in force of cardiac contraction and cardiac output without significant change in hea rate, peripheral resistance and BP. o In comparison to dopamine, dobutamine :? i Does not cause renal or mesentric vasodilation. ii Does not cause coronary vasoconstriction no effect on alpha receptors. iii Does not cause release of endogenous norepinephrine and does not precipitate arrythmia. If has an effect on peripheral resistance , always decreases it Dopamine can increase or decrease peripheral resistance depending on the dose. 