General description This certified reference material (CRM) is produced and certified in accordance with ISO/IEC 17025 and ISO Guide 34. Biochem/physiol Actions Endogenous neurotransmitter at adenosine receptors. Cardioprotective effects may relate to activation of A1 adenosine receptors. The antiplatelet and anti-inflammatory actions of adenosine appear to be mediated via the A2 adenosine receptor. In contrast, adenosine appears to be a pro-inflammatory mediator in asthma and chronic obstructive pulmonary disease (COPD).