Something basic - On Adenosine stress test
Adenosine causes vasodilation in the small and medium sized arterioles (less than 100 µm in diameter). When adenosine is administered it causes a coronary steal phenomenon, where the vessels in healthy tissue dilate as much as the ischemic tissue and more blood is shunted away from the ischemic tissue that needs it most. This is the principle behind adenosine stress testing.
Adenosine is quickly broken down by adenosine deaminase, which is present in red cells and the vessel wall.