Which vasodilator is associated with A2A receptor binding specifically?

The correct choice is linked to the chemistry of vasodilators and their specific receptor interactions. Regadenoson is designed as a selective agonist for the A2A adenosine receptor, which plays a significant role in cardiovascular pharmacology, particularly concerning diagnostic imaging and stress testing in nuclear medicine and PET imaging.

By binding specifically to the A2A receptor, regadenoson promotes vasodilation, which increases blood flow and enhances the delivery of radiopharmaceuticals to myocardial tissue, making it useful during PET scans to evaluate myocardial perfusion. Its selectivity is crucial because it minimizes side effects associated with non-selective adenosine receptor activation, leading to a better safety profile and more predictable responses during imaging procedures.

The other options mentioned, while they have relevance in cardiovascular responses, do not exhibit the same specificity for A2A receptors. Adenosine itself interacts with multiple receptor subtypes (A1, A2A, A2B, and A3), making it less specific than regadenoson, while dipyridamole functions primarily through the inhibition of adenosine uptake, thereby increasing endogenous adenosine levels rather than acting as a direct receptor agonist. Adenosine triphosphate,