http://uk.news.yahoo.com/21/20100530/thl-acupuncture-relief-link-identified-d831572.html A biological molecule that may help explain the effects of acupuncture has been identified by scientists. The chemical, adenosine, is a natural compound known for pain-killing and anti-inflammatory properties. It also influences the heart and plays a role in regulating sleep. Researchers found that adenosine is very active in tissues affected by acupuncture, the ancient Chinese treatment that involves inserting needles into sensitive points of the body. The scientists performed acupuncture on mice suffering chronic inflammatory pain in one paw. Each animal received a 30-minute treatment with fine needles inserted into a known acupuncture point near the knee. Acupuncture reduced discomfort by two-thirds in mice with normal levels of adenosine. However, it had no effect on "knock out" mice genetically prevented from responding to adenosine, the researchers found. During and immediately after acupuncture treatment, adenosine levels in the tissues near the needles were boosted 24-fold. Maiken Nedergaard, from the University of Rochester Medical Centre in New York state, said: "Acupuncture has been a mainstay of medical treatment in certain parts of the world for 4,000 years, but because it has not been understood completely, many people have remained sceptical. "In this work, we provide information about one physical mechanism through which acupuncture reduces pain in the body."