effects and healing mechanism
There is no simple answer to the question of how acupuncture works.
Numerous differentphysiological mechanisms stand at play when a particular acupuncture point or points are being activated by needling, moxibustion, etc.
Scientific research (see Links and References )has shown that acupuncture regulates several organ systems, by way of example:
Eliminates or relieves pain.
* Acupuncture and explicitly ear acupuncture balances over-activity or under-activity of various organs and tissues.
– This is due to modulation effectof acupunctureon central and peripheral nervous systemsCNS, PNS
Increases blood circulation locally as well as overall in the circulatory system:
* This can be observed as slight skin redness on the site of needling, and also the experience of the feeling of warmth during treatment session.
Strengthens the immune system:
* Originally, textbooks on acupuncture (before the Christ Era ) dealt with fever diseases, in fact, acupuncture itself developed as a result of handling of infectious diseases,
* In the West, however, acupuncture has been known mostly as pain control therapy,
* Nevertheless, resent research confirmed the correlation between CNS, endocrine system and acupuncture, namely, a benign increase of:
** Immunoglobulins (also called antibodies, part of adaptive immunity, are large Y-shape proteins produced by white blood cells and used by the immune system to identify and neutralise viruses and bacteria).
** NK cells (natural killercells, part of innate immunity, provide rapid response without the help of antibodies to virusinfected cells and tumourcells).
Provides calming effect:
This includes general relaxation, improved sleep, and anti-depressive effect.
One of the explanations of this action is acupuncture’s influence on adrenal glands, namely:
1. Its immediate effect on adrenal medula’s production of catecholamines:
* nadrenaline(epinephrine), noradrenaline(norepinephrine), and dopamine,
** these hormones have an effect on sympathetic NS:
(that is activated to mobilize physiological resources in stressful situation and thus stimulate activity of internal organs and tissues, including, increase in frequency and power of heart contraction, liver’s breakdown of glycogen, breakdown of fat in adipose tissue, contraction of blood vessels, etc,).
2. Its slower effect on adrenal cortex’s production of cortisol that have mobilizing effect on organs and tissues ad well as anti-inflammatory affect.
One of the mechanisms that lies behind the healing process of acupuncture(and some of the other TEAM therapies) is associated with connective tissue (to be more precise connective tissue proper) (read more in GuaSha).
Connective tissue (called Cou Li in Chinese terms) is one of the largest and most extensive body organs, where electrical, cellular and tissue remodelling signals are responsive to mechanical forces (acupuncture, acupressure, Gua Sha, cupping and massage, for example) as such being the mediator of therapeutic effect.
In the past decades thousands of clinical studies (both in the West and East) are devoted to the analgesic effectof acupuncture.
The result of these studies is a successful implementation ofthis traditional healing technique intowestern medical practice,by way of example:
In Western medicine, musculoskeletal disorders and labour pain are approached by physical therapists and obstetricians who are acquainted with acupuncture basics,
In some clinicsin Asia, the analgesic effect of acupuncture is mastered to the point where surgical intervention (be it a tonsillectomy or open heart surgery) does not longer require local or general anaesthesia.
Today, regardingthe healing mechanism of acupuncture, modern science (in the West as well as East Asia) has elaborated (to a definite extent)on its modulating effect that involves four major signalling networks of the body, that is:
1) Central nervous system, CNS:
* Communicates to other organ systems and body parts via release of neurotransmittersalong the neural pathways (electrical signalling),
* Stimulates other systems (e.g. endocrine system) thus resulting in the regulation of production of hormonesand cytokines.
2) Endocrine system:
* Communicates to other organ systems (foremost endocrine glands and target cells of various organs) via hormonesthat are transported by the blood (endocrine signalling).
3) Cell signalling system:
* Occurs viacytokines:
** (cytokine fr. Greek cyto "cell" + kinisi "movement",
** Aresmall proteins thatare produced by broad range of cells (e.g. immune cells, endothelial cells, fibroblasts, stromal cells, etc.) to communicate to neighbouring cells (paracrine signalling) or to signal about changes within themselves (autocrine signalling),
** Are transported viaintracellular fluid, extracellular fluid or blood, depending on the type of tissue they originate from.
4) Subcutaneous fascia (a form of connective tissue proper):
* Is a fibrous membrane, one of the largest and most extensive body organs, where electrical, cellular and tissue remodelling signals are responsive to mechanical forces (e.g. massage, acupuncture, Gua Sha, acupressure, cupping , etc.),
* Is found in between other tissues everywhere in the body (e.g. neural pathways, bloodand lymph tissue, and supportive tissue like cartilage and bone) and serves as a 'body-wide signaling network', that transmits mechanical signalsto and from the abundant fibroblasts, immune, vascular, and neural cells present within tissues (mechanical signalling).
Concerning effect of acupuncture on CNS, numerous clinical experiments (on animal as well as humans) were carried out with the goal to establish:
What neural pathways are involved,
Where along the neural pathways reconnection occurs, and,
What chemical messengers (neurotransmitters and hormones) are released by acupuncture stimulus.
It was found that body’s response to acupuncture stimulus occurs on various levels of CNS, depending on:
Manipulation method of an acupuncture needle (e.g. its unilateral (clockwise or counter clockwise) rotation or its electrical stimulation),
Pain experience that acupuncture evokes (as in the case of strong needle stimulation (e.g. rotation), or electrical needle stimulation),
If needling is performed on the same segment or another segment (body part that is innervated by same nerve rot in the spinal cord).
Response on the level of the peripheral NS (PNS):
Local neurotransmitters are released when needle pierces the skin and mechanoreceptors and nerve fibres get activated,
These chemical messengers activate electrical signals between neurons and include:
* Is a small protein that causes blood vessel dilation via release of three different molecules (as nitric oxidefor example, see below) and therefore causes blood pressure to fall,
* A neurotransmitter and neuromodulator,
* Is released from peripheral terminals of sensory nerves in the skin, muscles and joints and is associated with inflammatory processes and the transmission of pain information into the CNS.
* A widely expressed neurotransmitter that is found in the brain, spinal cord and intestinal tract and is predominantly involved in modulation and inhibition of action potentials (electrical stimulus) in neurons.
* Has been implicated in many biologically diverse functions, including: nociception (is the encoding and processing of harmful stimuli in the NS and, therefore, the ability of a body to sense potential harm), waking and sleep regulation, cognition, feeding, regulation of mood, regulation of blood pressure, it also has roles in development as well as acting as a cellular growth factor.
* Growth Hormone Release Inhibiting Factor GHIH,
* Is an inhibiting peptide hormone that regulates the endocrine system, inhibition of the release of numerous secondary hormones, neurotransmission, and cell proliferation.
* Is produced in the:
* Brain (where pituitary gland inhibits the production of growth hormone),
* Stomach (where it reduces the production of acid secretion and the release of gastric hormones, reduces smooth muscle contractions, and thus decreasing the rate of gastric emptying),
* Pancreas (where it inhibits insulin and glucagon secretion),
* Small intestine (where it reduces smooth muscle contractions and blood flow within the intestine).
* Is a vasoactive intestinal peptide,
* Its major role is to stimulate the secretion of water and electrolytes in the intestines,
* Also induces smooth muscle relaxation in the oesophagus, stomach and gall bladder,
* Inhibits gastric acid secretion and stimulates pepsinogen secretion,
* Stimulates production of sodium bicarbonate in the pancreas,
* Stimulates secretion of water into pancreatic juice and bile,
* Has a key role in communication between individual brain cells in the hypothalamus (in the brain), thus synchronizing the timing of hypothalamus’ function with the environmental light-dark cycle,
* Causes coronary vasodilation in the heart and has a positive inotropic (alters the force or energy of hearts muscular contractions) and chronotropic (change the heart rate) effect,
* Stimulates Growth Hormone secretion in the pituitary gland.
* Is Calcitonin Gene Related Peptide,
* Has vasodilatoryeffect (thus increasing lymphatic and blood circulation locally),
* Its low doses have anti-inflammatoryeffect.
* Is neurotransmitter that is produced in hypothalamus, stored in pituitary gland, and has receptors in many parts of the brain,
* Has acquired particular interest in the resent years studies, and is on the WHO’s Model List of Essential Medicines (alongside dopamine, for example),
* Plays an important role in the physiology of intimacy, sexual reproduction, and maternal behaviour,
* Inhibits the release of stress hormones, including adrenalin and cortisol,
* Resent clinical studies reveal its effects on some types of social behaviour, including pair bonding, trust, generosity and romantic attachment,
* Its releases also increases by touch, massage, application of warmth and during laughter.
Response on the level of the spinal cord:
The spinal cord has three major functions:
* motor signal transmission (e.g. hand motion) from the brain (CNS) to the internal organs and the extremities (i.e. to thePeripheralNS)
* sensory signal transmission (e.g. pain,touch) form the PNS and the internal organs to CNS
* coordination of certain reflexes (neuro circuit function)
When it comes to pain experience here the spinal cord functions according to Gate Control Theory1of pain:
* The theory was highly welcomed by acupuncture community since it canpartially explain the analgesic effect of acupuncture.
* Its main principle runs as follows:
** (In the spinal cord) non-painful stimulus (e.g. acupuncture) closes the “gates” to painful stimulus (e.g. tennis elbow), which prevents pain sensation from travelling to the CNS, and thus conscious experience of pain.
** The mechanism of treating pain(stimulus) with acupuncture (stimulus) can be described as a transmission of stimuli along two different nervous pathways:
*** on the level of the spinal cord, body prioritizes to let forth (forward) to the brain only one stimulus, a non-painful one, which is inthe case of acupuncture a needling and a manipulation of a point,
*** This is akin a train in a one-way-tunnel, where only one train can pass through at a time,
*** This means that pain-train will be stopped at the gate of the spinal cord, so far acupuncture has been administered, this explains a short term analgesic effect of acupuncture,
** At the gate the analgesic effect of dynorfin and enkephalin are also have been involved (see below),
** This theory, however, does not explain a long term effect of acupuncture that can last for week or months
** The long term affect is attributed to serotonin(see above)and noradrenalinrelease,
** Spinal cord also has receptors for dynorphin(the most powerful opioid neurotransmitter, others includeendorphins and enkephalins).
Response on the level of the parasympathetic nervous system, NS
* Mild stimulation of an acupuncture needle provides inhibiting (calming down)effect on the parasympathetic NS
** Part of autonomic NS that is activated to stress situations,
* Strong stimulation, on the other hand, activates parasympathetic NS:
* Mild stimulation of an acupuncture needle provides inhibiting effect on the parasympathetic NS.
Response on the level of HPA axis (Hypothalamic –Pituitary - Adrenal axis):
This neuro-hormonalrelationship has been reported in the resent year’s research on stress and involves the interplay between hypotolamus in the brain and its releasing factor that stimulates pituitary gland to release ACTH(adrenocorticotropic hormone):
* Regulates homeostasisin a wide range of physiological functions,
* Additionally, ACTHstimulates adrenal glands to secrete “stress hormone”cortisol:
* Mobilises for fight-or-flight response and also has a strong anti-inflammatory effect,
** However , its high levels in the blood have numerous harmful effects.
The calming affect that acupuncture has on the body, can be the result of modulation of HPA axis:
* Mild stimulation of an acupuncture needle provides an inhibiting effectofACTH release and consequently the release of cortisone,
* Strong stimulation - has an opposite, excitatory effect,
* The same effect is evoked inadrenal glands regarding the release of adrenaline and noradrenaline.
Response on the level of the brain:
* The reticular formation, RS(from Lt. rēticulāris,netlike) is considered to play central role, regarding the therapeutic effect of acupuncture, especially ear acupuncture,
* RS is a complex structure that has neurons in different parts of the brain,
* RS can inhibit or excite sensory or motor impulses and its stimulation can be exerted on the muscle tone, breathing, blood pressure, wakefulness(state of consciousness), etc.
– Being stimulated by acupuncture, RS exerts its systemic effect on the body by connecting following, important structures of CNS:
Summarising, the regulation of the major signalling systems by acupuncture provides myriad of physiological responses all of which work in synergy to achieve homeostasis, a balance in the flow of Qiand Blood, Yin-Yang and Internal organ ( Zang Fu) functions:
CNS: via regulation of neurotransmitters and neurohormones: e.g. endorphins, serotonin, GABA, oxytocin, somatostatin, dopamine,
Endocrine system: via regulation of hormones: e.g. adrenaline, noradrenaline, cortisol,
Cardiovascular activity: including regulation of blood pressure and blood vessel dilation, via regulation of e.g. bradykinin, dopamine, CGRP,
Gastrointestinal activity: viaserotonin, galanin, VIP, somatostatin, dopamine,
Blood composition: via regulation of serotonin,
Immune system activity: viaimmunoglobulins, NK cells, dopamine,
Inflammation viasubstance P, cortisol,CGRP, histamine,
Pain perception via endorphins, dynorphin, substance P.
Gate Control Theory:
Was proposed by leading British neuroscientist Patrick David Wall,described as 'the world's leading expert on pain”, and a Canadian physiologist Ronald Melzack who revolutionized pain research,
Led to the valuable discovery of endorphins and enkephalins, the body’s natural opiates.
Melzack's definition of pain has been adapted by the International Association for the Study of Pain.
* Pain is a multidimensional complex with numerous sensory, affective, cognitive, and evaluative components.