The present invention relates to methods for myocardial imaging by administering at least one 2-adenosine N-pyrazole, 2-adenosine C-pyrazole or a combination thereof A.sub.2A adenosine receptor agonist to a human undergoing myocardial imaging. The invention also relates to methods of producing coronary vasodilation without significant peripheral vasodilation by administering at least one 2-adenosine N-pyrazole, 2-adenosine C-pyrazole or a combination thereof adenosine A.sub.2A adenosine receptor agonist to a human.