How does acupuncture work? What is acupuncture’s mechanism of action? Today’s blog post explores these questions to help shed light on the mysteries of this ancient, powerful healing therapy.
Acupuncture’s Mechanism of Action
What happens when an acupuncture needle penetrates the skin? Traditional Chinese medicine (TCM) explains that a trained practitioner skillfully manipulates the needle, eliciting a “deQi” effect. The patient feels an achy sensation around the insertion area, reflecting high sensory and sympathetic nerve innervation acting on distal blood vessels more than proximal segments.
Such an anatomical effect accounts for the more robust autonomous responses associated with distal acupuncture points, especially those at the ends of the channels. A similar effect occurs with the notably higher concentration of sympathetic innervation in the feet.
Manipulation of acupuncture needles transforms connective tissue, altering the fibroblast structure. This change caused by the acupuncture needle results in the release of ATP. ATP is then further broken down into adenosine and other purines. ATP and adenosine act as anti-nociception agents blocking pain through purinergic receptors.
Acupuncture Point Activation
The achy sensation caused by stimulating an acupuncture needle is called Deqi. This feeling reflects the activation of Qi (vital energy) inside the channels. Often patients might experience a combination of sensations, including numbness, soreness, distention, or heaviness during acupuncture needle stimulation.
Deqi is mentioned in Chapter 1 of the Huang Di Nei Jing Ling Shu and means “the arrival of vital energy.” Eliciting Deqi at the acupuncture point plays an essential role in achieving the therapeutic effect of acupuncture treatment. Acupuncture’s mechanism of action always involves the activation of Deqi on an acupoint.
A functional magnetic resonance imaging (fMRI) study showed increased blood flow to the acupoints linked to the sensation of Deqi. Another study found that the different intensity of acupuncture sensations influences the analgesic effect. Finally, a third study concluded that real acupuncture produces a stronger Deqi sensation and better clinical outcomes than sham acupuncture.
Acupuncture Needle Grasp
The phenomenon of needle grasp is another component of acupuncture’s mechanism of action. It is described as a tug on the needle, like a fish biting on a fishing line, creating a tight mechanical coupling between needle and tissue. Multiple studies confirm that the needle grasp perceived by acupuncturists directly corresponds to the sensation of Deqi, which patients also feel. This effect plays an essential role in the therapeutic mechanism of acupuncture.
Investigators have hypothesized that the needle manipulation (by rotation or thrusting movement) causes needle grasp, and hence, Deqi results from collagen and elastic fibers winding and tightening around the needle. In addition, the higher density of connective tissues at acupuncture points might explain the occurrence of needle grasp.
Needle grasp allows further movements of the needle to pull and influence the connective tissue surrounding the needle, delivering some of its effects through mechanical influence on the connective tissue matrix. In addition, manipulating the acupuncture needle causes remodeling of fibroblasts in the connective tissue.
Acupuncture and Afferent Nerve Fibers
Previously, some randomly controlled research studies claimed a lack of significant difference between real and sham acupuncture. This false conclusion arose from the fact that both real and sham acupuncture involves tactile stimulation. The reason behind such an effect is the stimulation of the afferent nerve fibers.
The superficial pressure induced by sham needling intervention can significantly affect the brain’s limbic system. In addition, acupuncture fMRI studies have shown that both tactile stimulation and acupuncture manipulation activate neural activities and thus might have a potential effect on pain modulation.
The human tactile sensation is moderated primarily by large myelinated afferents (Aα and Aβ). Alternatively, pain and temperature sensations arise from small myelinated (Aδ fiber) and unmyelinated (C fiber) afferents. Therefore, it is plausible that sham acupuncture, used as a control procedure in acupuncture studies, activated this group of afferents and produced analgesic effects. In other words, sham acupuncture may produce a weak but measurable force through acupuncture’s mechanism of action on the nervous system.
Acupuncture Analgesic Effect
Extensive research documents acupuncture’s analgesic effect in pain management. The gate control theory of pain, which was proposed by Melzack and Wall back in 1965, and later by Melzack, suggested that the stimulation by the acupuncture needle activates the inhibitory brainstem system and therefore blocks pain signals.
In addition, many research studies document the release of endogenous opioids and ATP triggered by an acupuncture needle. This data suggests a link between acupuncture and signaling mediated by neurotransmitters.
Acupuncture More Powerful than Morphine
Endorphins are amongst the most studied neurotransmitters in acupuncture research. This is because they are more potent in pain relief than exogenous morphine. A recent study conducted by Grissa et al. compared the effectiveness of acupuncture versus morphine in the management of acute pain in the emergency department.
Investigators observed a 92% reduction of pain in patients treated with acupuncture, while morphine-treated patients experienced only a 78% reduction. Furthermore, acupuncture-treated patients had a much faster pain recovery time (an average of 16 minutes compared to 28 minutes in the morphine control group).
ATP as Neurotransmitter
Researchers identified adenosine triphosphate (ATP) in 1929, noting its effects on heart excitability, lowering of blood pressure, and coronary vasodilation. In 1954 investigators identified ATP as a neurotransmitter in the somatosensory system, demonstrating that ATP derived from peripheral endings of primary sensory neurons.
Numerous investigations over the years confirmed the signaling function of ATP in peripheral tissues, leading to the discovery of Purinergic Signaling, which consists of neurotransmission by purinergic receptors.
In 2009, Burnstock addressed acupuncture’s mechanism of action by proposing that acupuncture needles trigger the release of a large quantity of ATP from cells in the skin. Specifically, ATP activates P2X ligand-gated ion channel 3-receptors located on sensory nerves. The resulting signals modulate the CNS pathways responsible for the conscious awareness of pain.
Adenosine and the Sensory Nervous System
Energy in the form of ATP is one of the essential requirements for our body to function. Adenosine, the core molecule of ATP, forms a unique link among cell energy, gene regulation, and neuronal excitability. Specific receptors which regulate neuronal and non-neuronal cell functions recognize adenosine.
As a neurotransmitter, adenosine regulates pain transmission in the spinal cord and the periphery. In addition, adenosine acts as an endogenous anti-inflammatory agent, playing an essential role as a signaling molecule in immunity and inflammation. As a result, nearly every aspect of cell function involves adenosine.
Acupuncture, ATP, and Deqi
New acupuncture research recently identified adenosine as a mediator of anti-nociceptive properties (the body’s response to potentially toxic stimuli, like harmful chemicals or traumatic injury, by the sensory nervous system). Another study conducted by the same group demonstrates the increased release of adenosine and ATP at stimulated acupuncture points. Both studies show that the concentration of interstitial purines increased by mechanical stimulation from the acupuncture needle (activating Deqi).
Next Steps
Try acupuncture if you struggle with pain or a health condition not responding to Western treatment. Acupuncture is safe with no adverse side effects, and treatments are relaxing.
BOOK NOW to schedule an appointment online.
Meet the Practitioners (VIDEO)
Focus Keyphrase: Acupuncture’s Mechanism of Action
Photo by Andrea Piacquadio: https://www.pexels.com/photo/joyful-adult-daughter-greeting-happy-surprised-senior-mother-in-garden-3768131/
What our Clients are Saying
I’m a golfer and started having trouble with my left shoulder over a year ago. My doctor wanted to do surgery, but I wanted to try other alternatives first. So I tried acupuncture. The folks at Raleigh Acupuncture were very professional, reasonably priced and did excellent work. They resolved my shoulder pain completely. I use them now for other pains in my post-50 body! Thank you Raleigh Acupuncture.
I’m a dentist and over the last 20 years the nature of my work and positions required by my work had resulted in chronic neck pain. It affected my sleep, limited my ability to exercise, and was just a real pain in the neck! A friend at church recommended Raleigh Acupuncture and I gave it a try. I have to say that I was a bit skeptical, but gave it a try because I had tried a number other therapies with no success. I’m glad I did. They resolved my neck pain completely!
All of my joints were hurting. I’ve got fibromyalgia and it effects me by making my joints hurt. The pain would move around from place to place, first the hip, the next day the shoulder, then the knee, etc. The practitioner at Raleigh Acupuncture explained that the best way to treat my kind of moving joint pain was to treat me holistically. Instead of treating the hip one day, the shoulder the next, they treated the root of the pain. They said this type of treatment would also improve my mood and my sleep. Right on all counts. I started feeling better after the second treatment. It’s like all of the joints just settled down and stopped giving me trouble. I had less flares and the intensity of the pain went way down. My sleep is better, not just because I have less pain. I’m more relaxed and less stressed. I’ve made this treatment a regular part of my life. I’m very grateful.
I suffered from low back pain for years and tried many different remedies. When I came to Raleigh Acupuncture, they really listened to understand my issues. I can honestly say that they cured my chronic back pain. I didn’t think it was possible, after all these years. I highly recommend this practice. The doctors take the time and do good work.