Effect of dopamine on local segment work and O(2) consumption in collateral-dependent myocardium

Dopamine exerts a depressed functional response in collateral-dependent myocardium without excluding O2 supply and restricting consumption. The functional impairment is confined to myocytes. Dopamine stimulates alpha and beta adrenergic receptors and dopaminergic receptors in myocardium indicating that cellular mechanisms are involved in the depressed responsiveness caused by dopamine stimulation.