This review summarizes clinical application of
adenosine and
adenosine 5'-triphosphate (
ATP) in
pain conditions. Investigations have been performed in patients with acute perioperative
pain or chronic
neuropathic pain treated with intravenous
adenosine or
ATP, or intrathecal
adenosine. Characteristic central
adenosine A1 receptor-mediated
pain-relieving effects have been observed after intravenous
adenosine infusion in human
inflammation/sensitization
pain models and in patients with chronic
neuropathic pain.
Adenosine compounds, in low doses, can reduce
allodynia/
hyperalgesia more consistently than spontaneous
pain, suggesting that these compounds affect neuronal pathophysiological mechanisms involved in central sensitization. Such
pain-relieving effects, which are mostly mediated via central
adenosine A1 receptor activation, have a slow onset and long duration of action, lasting usually for hours or days and occasionally for months. With acute perioperative
pain, treatment with a low-dose infusion of
adenosine compounds and the A1 receptor-mediated central antisensitization mechanisms may play only a minor part in the total perioperative
pain experience. By administering sufficient doses of
adenosine compounds during surgery, however, significant and long-lasting perioperative
pain relief can be achieved via central A1 receptor-mediated antinociceptive/
analgesic actions as well as via peripheral A2a or A3 receptor-mediated antiinflammatory actions. Thus,
adenosine compounds have significant potential for alleviating various types of
pain.