Pain relief is a common function of acupuncture, but in the past people are not very clear about its scientific principles. A recent study in the United States that acupuncture can prompt the body to release a natural painkiller, thus playing the effect of pain relief. The new issue of the British “Nature Neuroscience” magazine published a report that the University of Rochester and other institutions in the United States, researchers through animal experiments found this principle. They have a paw uncomfortable experimental rats corresponding knee parts for about half an hour of acupuncture, the results found that this will lead to the experimental rats body to release a kind of material called adenosine, this material has a natural painkilling effect, can reduce the pain of experimental rats. Tests showed that the amount of adenosine in the corresponding area after acupuncture was more than 24 times higher than before acupuncture. To further verify this finding, the researchers also used a drug that makes it difficult for the body to eliminate adenosine naturally on the lab rats. The results showed that the accumulation of adenosine in the body increased significantly after the use of this drug, and the effective time of acupuncture for pain relief was extended to more than three times. Dr. Nedergaard, who participated in the study, said that acupuncture has a long history of treatment, but because its principle of action has been less clear, many people are skeptical of acupuncture, and the current study reveals that there is indeed a scientific principle of acupuncture pain relief.