Nitric oxide and why acupuncture works

Science has provided some information about why acupuncture can help with pain in muscles, tendons and other areas of the body. And it’s all to do with nitric oxide.
Apparently the endothelium (inner lining) of blood vessels uses nitric oxide to signal the surrounding smooth muscle to relax, thus resulting in vasodilation (the widening of blood vessels) and increasing blood flow. Nitric oxide is highly reactive (having a lifetime of a few seconds), yet diffuses freely across membranes.
The researchers found that acupuncture and heat which could be from moxabustiin can lead to elevated levels of nitric oxide in the skin at the "acupoints" where the needles are inserted and manipulated. They noted that nitric oxide increases blood flow and encourages the release of analgesic or sensitizing substances, which causes the skin to feel warmer and contributes to the beneficial pain reducing effect of the therapies.
It’s good to know that after nearly 2000 years of use, science is contributing to an understanding of why acupuncture and moxabustion works.