A1 receptors are implicated in sleep promotion by inhibiting wake-promoting cholinergic neurons in the basal forebrain.

[citation needed] ((R)-tetrahydrofuran-3-ylamino)-9H-purin-9-yl)-tetrashydrofuran3,4-diol) [9] In the heart, A1 receptors play roles in electrical pacing (chronotropy and dromotropy), fluid balance, local sympathetic regulation, and metabolism.

[18] Norepinephrine is a positive chronotrope, inotrope, and dromotrope, through its agonism of β adrenergic receptors on pacemaker cells and ventricular myocytes.

However, in altered cardiac function, such as hypoperfusion caused by hypotension, heart attack or cardiac arrest caused by nonperfusing bradycardias, adenosine has a negative effect on physiological functioning by preventing necessary compensatory increases in heart rate and blood pressure that attempt to maintain cerebral perfusion.

[21] Thus, intravascular administration of adenosine increases the amount of glucose and lactate available in the blood for cardiac myocytes.

A1AR activation also partially inhibits glycolysis, slowing its rate to align with oxidative metabolism, which limits post-ischemic damage through reduced H+ generation.