Analgetic and algetic effects of adenosine in healthy volunteers and patients with coronary disease

Abstract: Background Adenosine is a bimodal neuromodulator with algesic and analgesic effects. The different effects of adenosine are partly due to the route of administration. Low-dose adenosine infusion induces analgesia at the same magnitude as morphine, while adenosine as bolus injection induces chest pain, similar in character as angina pectoris. AIMS To evaluate algesic / analgesic and preconditioning effects of adenosine in patients with silent myocardial ischemia or angina pectoris and healthy volunteers and the possible gender differences and opioid effect on the adenosine-provoked pain. Methods and results In paper I, the tolerance to adenosine-provoked pain was tested in patients with silent myocardial ischemia, angina pectoris and healthy volunteers. Patients with silent myocardial ischemia had higher pain threshold compared to the other two groups. This difference was not modified by opioid antagonist, naloxone. In paper II, the hemodynamic and pain response to high-dose adenosine infusion and the effects of an exogenous opioid agonist,