Research, especially the mechanistic investigations on acupuncture analgesia, has yielded abundant information showing that acupuncture signal, either generated by manual acupuncture or electroacupuncture (Ea), remarkably influences the release, synthesis, reuptake, and degradation of the central neurotransmitters/modulators. This includes monoamines (eg. serotonin, noradrenalin, and dopamine), acetylcholine (ACh), amino acids, orphanin FQ, substance P, prostaglandin, cholecystokinin-octapeptide-8 (CCK-8), somatostatin, and neurotrophic factors.
In general, acupuncture enhances the activity of the endogenous opioid peptides, serotonin, dopamine, ACh, and inhibitory amino acids such as aminobutyric acid (GABa), glycine, taurine, and lactamine, while it attenuates the activity of noradrenaline and excitatory amino acids, including glutamate and aspartic acid. A prolonged period of acupuncture may induce excessive production of CCK-8 and deplete some pro-acupuncture substances, thus causing the so-called acupuncture tolerance.
Acupuncture also regulates the expression and function of the corresponding receptors. However, the effects of acupuncture on the central neurotransmitters/modulators are dependent on the status of the organism and conditions of acupuncture (eg. stimulation parameters and acupoints), and vary from region to region in the central nervous system. Although this data was largely obtained from the studies on acupuncture analgesia, it is reasonable to presume that acupuncture is capable of modulating the brain functions through the regulation of central neurotransmitters/modulators, because all the acupuncture-influenced neurotransmitters/modulators participate directly or indirectly in neural regulation in almost all aspects.
Acupuncture enhances the synaptic dopamine availability to improve motor function in Parkinson’s disease. This has been proven as a scientific study in which acupuncture is given at acupoint GB.34 by increasing dopamine release.Acupuncture rescues cognitive impairment and upregulates dopamine in patients with cerebral infarction which often leads to mild cognitive impairment. It may be used as an additional therapy to conventional western treatment to improve the clinical outcome of the patient with post cerebral infarction memory loss.
Randomized controlled trial with acupuncture has been shown to reduce preoperative anxiety. Acupuncture is also useful in treating insomnia and anxiety. A scientific study shows that after five weeks of acupuncture treatments, there was a significant nocturnal rise in melatonin secretion, as measured in the urine and significant improvement in sleep onset, total sleep time, sleep efficiency and anxiety score. Psychological symptoms associated with opioid addiction have been scientifically proven to get better with acupuncture. These symptoms include anxiety and depression, and are often associated with the initiation and use of opioids.
Recently electro-acupuncture has been used to relieve the behavioural signs of withdrawal in addicts. Auricular acupuncture has also been used very effectively in treating anxiety, insomnia, depression, smoking and alcohol addiction. Common ear acupuncture points used for treating withdrawal symptoms include shen men, kidney, liver, lower lung (L) and sympathetic point.
The author is Head of the Department of Acupuncture, Sir Ganga Ram Hospital, Delhi