[Possible Living Factors Influencing the Efficacy of Acupuncture Analgesia Between Chinese and Western Populations:Caffeine].

It has been known for thousands of years that acupuncture can relieve pain. However, the efficacy of acupuncture analgesia (AA) now has to be reconsidered due to negative reports from western countries. In the present study, the possible correlation between caffeine and the difference in AA in China and western countries was determined using the following factors:1) caffeine and pain; 2) adenosine, adenosine receptor and caffeine; 3) AA and caffeine. As a non-selective antagonist of the adenosine receptor, caffeine at low doses can be used as an adjuvant analgesic, and can augment antinociception combined with other analgesics. Caffeine can act as an important neural modulator, and adenosine can produce antinociception when combined with the A1 receptor located in spinal, supraspinal and peripheral tissue. A preclinical study demonstrated that caffeine at moderate doses could inhibit AA efficacy following plantar incision surgery in a mouse model. Caffeine is present in various foods, especially coffee, and approximately 85% of adults in western countries consume coffee regularly. Therefore, by reconsidering the correlation between caffeine, adenosine receptor and AA, and by determining the possible relationship between caffeine intake habits and AA efficacy, these findings will demonstrate the differences in AA between Chinese and western populations.