Evidence from brain imaging with fMRI supporting functional specificity of acupoints in humans

Effects of acupuncture and acupressure of the acupoint compared to the tendon on the blood circulation of human tendon in vivo

PURPOSE

The purpose of this study was to compare the effects of acupuncture and acupressure of acupoints on tendon blood circulation with those of both types of stimulation of tendon itself.

METHODS

Before, during (except for acupressure), and after acupuncture and acupressure of the tendon and acupoint, blood circulation of the Achilles tendon was measured using red laser lights.

RESULTS

The blood volume of the treated and non-treated tendons increased after acupuncture of the tendon (effect of time p = 0.030), whereas that tended to increase after acupuncture of the acupoint (effect of time p = 0.063). In addition, no significant difference in the increases in blood volume was found among the four conditions, i.e., after acupuncture stimulation of the tendon and acupoint for the treated and non-treated tendons (p = 0.492). The blood volume of the treated tendon significantly increased after acupressure of the tendon (effect of time p < 0.001), but not of the acupoint (effect of time p = 0.260), whereas that of the non-treated tendon did not change after acupressure of both the tendon and acupoint.

CONCLUSION

These results suggested that acupuncture of the tendon and acupoint acted centrally to enhance blood circulation of both the treated and non-treated tendons during the recovery period, whereas acupressure of the tendon locally increased blood circulation of the treated tendon only, but not the non-treated tendon and both the treated and non-treated tendons after acupressure of acupoint.

The mechanistic basis for the effects of electroacupuncture on neuropathic pain within the central nervous system

Nociceptive signaling responses to painful stimuli are transmitted to the central nervous system (CNS) from the afferent nerves of the periphery through a series of neurotransmitters and associated signaling mechanisms. Electroacupuncture (EA) is a pain management strategy that is widely used, with clinical evidence suggesting that a frequency of 2-10 Hz is better able to suppress neuropathic pain in comparison to higher frequencies such as 100 Hz. While EA is widely recognized as a viable approach to alleviating neuralgia, the mechanistic basis underlying such analgesic activity remains poorly understood. The present review offers an overview of current research pertaining to the mechanisms whereby EA can alleviate neuropathic pain in the CNS, with a particular focus on the serotonin/norepinephrine, endogenous opioid, endogenous cannabinoid, amino acid neurotransmitter, and purinergic pathways. Moreover, the corresponding neurotransmitters, neuromodulatory compounds, neuropeptides, and associated receptors that shape these responses are discussed. Together, this review seeks to provide a robust foundation for further studies of the EA-mediated alleviation of neuropathic pain.

Effect of Acupuncture on Time-Dependent of Muscle Endurance in Female Elbow Joint: A Randomized Controlled Trial

Immediate characteristics of acupuncture have been confirmed by relevant studies; however, the current study on the time effect of acupuncture in improving upper limb forearm muscle endurance is still limited. The aims of this study are to explore: (1) whether real acupuncture (RA) can improve female forearm muscle endurance compared to sham acupuncture (SA) and (2) whether the changes in forearm muscle endurance after RA are time-dependent. Thirty-six healthy female students were recruited to participate in isokinetic tests of elbow flexion/extension (Flex/Ext) from maximum flexion to maximum extension as much as possible using an isokinetic dynamometer at a speed rate of 60°/sec. Participants in the RA group were stimulated at Quchi (LI11), Shousanli (LI10), Hegu (LI4), Xiaohai (SI8), Tianjing (SJ10), and Waiguan (SJ5) acupoints for 20 min, while the SA group needling was near at these acupoints. The values of the isokinetic parameters and surface electromyography (sEMG) signals were recorded before and after acupuncture. After RA, the isokinetic parameters values (average torque, work, power, and speed), the sEMG values at four major muscles, and the joint stiffness of elbow Flex/Ext were significantly increased (p < 0.05). The enhancement of forearm muscle endurance lasted approximately 7–21 min (from post1 to post3/post4), indicating that the effect of RA to improve elbow Flex/Ext muscle endurance is time-dependent. Therefore, this study found that RA can immediately improve the forearm muscle endurance of healthy women compared with SA, and this effect can last approximately 7–21 min until the acupuncture efficacy decreased or disappeared.

Obesity Animal Models for Acupuncture and Related Therapy Research Studies

Obesity and related diseases are considered as pandemic representing a worldwide threat for health. Animal models are critical to validate the effects and understand the mechanisms related to classical or innovative preventive and therapeutic strategies. It is, therefore, important to identify the best animal models for translational research, using different evaluation criteria such as the face, construct, and predictive validity. Because the pharmacological treatments and surgical interventions currently used for treating obesity often present many undesirable side effects, relatively high relapse probabilities, acupuncture, electroacupuncture (EA), and related therapies have gained more popularity and attention. Many kinds of experimental animal models have been used for obesity research studies, but in the context of acupuncture, most of the studies were performed in rodent obesity models. Though, are these obesity rodent models really the best for acupuncture or related therapies research studies? In this study, we review different obesity animal models that have been used over the past 10 years for acupuncture and EA research studies. We present their respective advantages, disadvantages, and specific constraints. With the development of research on acupuncture and EA and the increasing interest regarding these approaches, proper animal models are critical for preclinical studies aiming at developing future clinical trials in the human. The aim of the present study is to provide researchers with information and guidance related to the preclinical models that are currently available to investigate the outcomes of acupuncture and related therapies.

Effect of Acupuncture on Timeliness of Male Shoulder Joint Endurance

Acupuncture as a traditional and commonly used treatment has been used to improve the performance of athletes. In the improvement of female shoulder joint explosive force and muscle endurance also has an immediate effect. However, whether the effect of acupuncture therapy can be maintained after improving athletic performance still worth further discussion. The purpose of this study was to explore the timeless of the physical neurophysiological response induced by acupuncture at specific acupoints in improving endurance performance. Seventeen healthy male participants completed six groups of shoulder joint isokinetic exercises. The isokinetic exercise completed in the first group was taken as the baseline. After acupuncture for 15 min, the following 5 isokinetic experiments were completed. Acupuncture acupoints included Binao (LI14), Jianliao (SJ14), Naohui (SJ13), Zhongfu (LU1), Xiabai (LU4), Tianfu (LU3) and Xiaoluo (SJ12). The results show that acupuncture can improve physical performance for 10–20 min. After acupuncture, the maximum torque, average power, average work and total work values significantly increased (p < 0.05). Stimulation of acupoints can effectively improve the performance of periarticular muscle endurance around the shoulder, but this improvement is limited by time.

Acupoint-brain (acubrain) mapping: Common and distinct cortical language regions activated by focused ultrasound stimulation on two language-relevant acupoints

Acupuncture, taking the advantage of modality-specific neural pathways, has shown promising results in the treatment of brain disorders that affect different modalities such as pain and vision. However, the precise underlying mechanisms of within-modality neuromodulation of acupoints on human high-order cognition remain largely unknown. In the present study, we used a non-invasive and easy-operating method, focused ultrasound, to stimulate two language-relevant acupoints, namely GB39 (Xuanzhong) and SJ8 (Sanyangluo), of thirty healthy adults. The effect of focused ultrasound stimulation (FUS) on brain activation was examined by functional magnetic resonance imaging (fMRI). We found that stimulating GB39 and SJ8 by FUS evoked overlapping but distinct brain activation patterns. Our findings provide a major step toward within-modality (in this case, language) acupoint-brain (acubrain) mapping and shed light on to the potential use of FUS as a personalized treatment option for brain disorders that affect high-level cognitive functions.

Outcome Prediction in Unresponsive Wakefulness Syndrome and Minimally Conscious State by Non-linear Dynamic Analysis of the EEG

Objectives: This study aimed to investigate the role of non-linear dynamic analysis (NDA) of the electroencephalogram (EEG) in predicting patient outcome in unresponsive wakefulness syndrome (UWS) and minimally conscious state (MCS).

Methods: This was a prospective longitudinal cohort study. A total of 98 and 64 UWS and MCS cases, respectively, were assessed. During admission, EEGs were acquired under eyes-closed and pain stimulation conditions. EEG nonlinear indices, including approximate entropy (ApEn) and cross-ApEn, were calculated. The modified Glasgow Outcome Scale (mGOS) was employed to assess functional prognosis 1 year following brain injury.

Results: The mGOS scores were improved in 25 (26%) patients with UWS and 42 (66%) with MCS. Under the painful stimulation condition, both non-linear indices were lower in patients with UWS than in those with MCS. The frontal region, periphery of the primary sensory area (S1), and forebrain structure might be the key points modulating disorders of consciousness. The affected local cortical networks connected to S1 and unaffected distant cortical networks connecting S1 to the prefrontal area played important roles in mGOS score improvement.

Conclusions: NDA provides an objective assessment of cortical excitability and interconnections of residual cortical functional islands. The impaired interconnection of the residual cortical functional island meant a poorer prognosis. The activation in the affected periphery of the S1 and the increase in the interconnection of affected local cortical areas around the S1 and unaffected S1 to the prefrontal and temporal areas meant a relatively favorable prognosis.

Effects of Acupuncture on Explosive Force Production by the Healthy Female Shoulder Joint

Background

Acupuncture is often used to treat chronic conditions, such as pain. In recent years, given the importance of the explosive forces generated by shoulder muscles for the completion of motor tasks, studies in which nerves were stimulated through acupuncture to increase the explosive forces were conducted. This study explored the effect of acupuncture on explosive force production by the muscles of the female shoulder joint.

Methods

Eighteen healthy women underwent shoulder adduction (Add), abduction (Abd), flexion (Flex), and extension (Ext) tests with an isokinetic measurement system. Acupuncture was used to stimulate the Zhongfu (LU1), Tianfu (LI3), Xiabai (LU4), Binao (LI14), Naohui (SJ13), Jianliao (SJ14), and Xiaoluo (SJ12) points, and electromyography (EMG) signals were recorded before and after acupuncture.

Results

After acupuncture, there was a significant difference in the average maximum work, the average maximum power, the average maximum speed, the total work in Add/Abd and Flex/Ext, the EMG signals, and the stiffness of the muscles in Abd and Ext (P < 0.05). There were no significant differences in the average maximum torque in Abd or Flex.

Conclusion

Based on the results, there may be a significant correlation between the manipulation of different acupoints by acupuncture and the average maximum torque and stiffness. Acupuncture may stimulate nerves to activate muscles and induce a postactivation potentiation effect that improves explosive force production. Therefore, acupuncture as an auxiliary tool may increase the explosive forces generated by acupoint-related muscles by stimulating nerves.

Does the Acupoint Specificity Exist? Evidence from Functional Neuroimaging Studies

BACKGROUND

Using functional neuroimaging techniques to explore the central mechanism of acupoint specificity, the key of acupuncture theory and clinical practice, has attracted increasing attention worldwide. This review aimed to investigate the current status of functional neuroimaging studies on acupoint specificity and explore the potential influencing factors for the expression of acupoint specificity in neuroimaging studies.

METHODS

PubMed database was searched from January 1st, 1995 to December 31st, 2016 with the language restriction in English. Data including basic information, methodology and study results were extracted and analyzed from the eligible records.

RESULTS

Seventy-nine studies were finally enrolled. 65.8% of studies were performed in China, 73.4% of studies were conducted with healthy subjects, 77.2% of studies chose manual acupuncture as the intervention, 86.1% of studies focused on the instant efficacy and 89.9% of studies used functional magnetic resonance imaging as scanning technique. The average sample size was 16 per group. The comparison of verum acupoints and sham acupoints were the main body of acupoint specificity researches. 93.7% of studies obtained the positive results and favored the existence of acupoint specificity.

CONCLUSION

This review affirmed the existence of acupoint specificity and deemed that the acupoint specificity was relative. Multiple factors such as participants, sample size, acupoint combinations, treatment courses, and types of acupoint could influence the expression of acupoint specificity.

Transcranial Direct Current Stimulation Over Prefrontal Areas Improves Psychomotor Inhibition State in Patients With Traumatic Brain Injury: A Pilot Study

Objectives

Many post-traumatic patients with minimally conscious state are complicated by psychomotor inhibition state (PIS), which impedes further rehabilitation. The treatment of PIS is not satisfactory. This pilot study aimed to investigate effects of anodal transcranial direct current stimulation (A-tDCS) on PIS in post-traumatic patients and examine the altered cortical activation after tDCS using non-linear electroencephalogram (EEG).

Methods

The study included 10 patients with post-traumatic PIS. An A–B design was used. The patients received 4 weeks of sham tDCS during Phase A, and they received A-tDCS over the prefrontal area and left dorsolateral prefrontal cortex (DLPFC) for 4 weeks (40 sessions) during Phase B. Conventional treatments were administered throughout both phases. JFK Coma Recovery Scale-Revised (CRS-R), apathy evaluation scale (AES), and the EEG non-linear indices of approximate entropy (ApEn) and cross approximate entropy (C-ApEn) were measured before Phase A, before Phase B, and after Phase B.

Results

After A-tDCS treatment, CRS-R and AES were improved significantly. ApEn and C-ApEn results showed that the local cortical connection of bilateral sensorimotor areas with their peripheral areas could be activated by affected painful stimuli, while bilateral cerebral hemispheres could be activated by the unaffected painful-stimuli condition. Linear regression analysis revealed that the affected sensorimotor cortex excitability and unaffected local and distant cortical networks connecting the sensorimotor area to the prefrontal area play a major role in AES improvement.

Conclusion

A-tDCS over the prefrontal area and left DLPFC improves PIS. The recovery might be related to increased excitability in local and distant cortical networks connecting the sensorimotor area to the prefrontal area. Thus, tDCS may be an alternative treatment for post-traumatic PIS.

Changes in Blood Circulation of the Tendons and Heart Rate Variability During and After Acupuncture

Objective: The purpose of this study was to investigate the changes in blood circulation of tendons and heart rate variability (HRV) during and after acupuncture in order to elucidate the mechanisms of acupuncture-induced changes in tendon blood circulation. Materials and Methods: During 10 minutes of acupuncture treatment and a recovery period of 40 minutes, blood volume (THb) and oxygen saturation (StO₂) of treated and nontreated tendons were measured using red laser lights. In addition, HRV was also measured during the experimental period. Results: THb and StO₂ of the treated tendons significantly increased during acupuncture, and then remained high during the recovery period. THb and StO₂ of the nontreated tendons did not change during acupuncture but gradually increased during the recovery period. In addition, the increase in THb of the nontreated tendons were significantly correlated with that of the treated tendons during the latter half of the recovery period. Heart rate (HR) continued to decrease during acupuncture and suddenly returned to the initial level after removal of the needle. The low-frequency (LF)/high-frequency (HF) ratio tended to increase during the recovery period. During the latter half of the recovery period, the changes in THb for both the treated and nontreated tendons were negatively correlated with the change in HR but not with changes in the LF/HF ratio. Conclusions: These results suggest that changes in blood circulation of tendons after acupuncture treatment were controlled by the autonomic nervous system, which could not be detected by HRV analysis.

Effects of Acupuncture Therapy on MCI Patients Using Functional Near-Infrared Spectroscopy

Acupuncture therapy (AT) is a non-pharmacological method of treatment that has been applied to various neurological diseases. However, studies on its longitudinal effect on the neural mechanisms of patients with mild cognitive impairment (MCI) for treatment purposes are still lacking in the literature. In this clinical study, we assess the longitudinal effects of ATs on MCI patients using two methods: (i) Montreal Cognitive Assessment test (MoCA-K, Korean version), and (ii) the hemodynamic response (HR) analyses using functional near-infrared spectroscopy (fNIRS). fNIRS signals of a working memory (WM) task were acquired from the prefrontal cortex. Twelve elderly MCI patients and 12 healthy people were recruited as target and healthy control (HC) groups, respectively. Each group went through an fNIRS scanning procedure three times: The initial data were obtained without any ATs, and subsequently a total of 24 AT sessions were conducted for MCI patients (i.e., MCI-0: the data prior to ATs, MCI-1: after 12 sessions of ATs for 6 weeks, MCI-2: another 12 sessions of ATs for 6 weeks). The mean HR responses of all MCI-0–2 cases were lower than those of HCs. To compare the effects of AT on MCI patients, MoCA-K results, temporal HR data, and spatial activation patterns (i.e., t-maps) were examined. In addition, analyses of functional connectivity (FC) and graph theory upon WM tasks were conducted. With ATs, (i) the averaged MoCA-K test scores were improved (MCI-1, p = 0.002; MCI-2, p = 2.9e^–4); (ii) the mean HR response of WM tasks was increased (p < 0.001); and (iii) the t-maps of MCI-1 and MCI-2 were enhanced. Furthermore, an increased FC in the prefrontal cortex in both MCI-1/MCI-2 cases in comparison to MCI-0 was obtained (p < 0.01), and an increasing trend in the graph theory parameters was observed. All these findings reveal that ATs have a positive impact on improving the cognitive function of MCI patients. In conclusion, ATs can be used as a therapeutic tool for MCI patients as a non-pharmacological method (Clinical trial registration number: KCT 0002451 https://cris.nih.go.kr/cris/en/).

Fascial neuromodulation: an emerging concept linking acupuncture, fasciology, osteopathy and neuroscience

According to Traditional Chinese Medicine “acupuncture is believed to restore the balance between Yin and Yang” and this can be understood in the Western medicine terminology as a “modulation of the equilibrium between parasympathetic and sympathetic activity”. The vast majority of studies concerning the mechanisms of action of acupuncture have been conducted on its influence on pain, and it has been proposed that acupuncture may indirectly relieve chronic pain by its effects on autonomic nervous system function. Several studies have shown that acupuncture recruits brain networks involved in the integration of multiple other brain functions: for example, the limbic-paralimbic-neocortical network, which plays a major role in modulating the affective dimensions of pain processing and the integration of emotional, sensorimotor, autonomic and immunological functions. It has been recently proposed that mechanical signaling through the connective tissue, along with transmission of the matrix deformation through the fascial system network, can explain the therapeutic effect of acupuncture. This model of acupunture, which involves the transduction of mechanical signals through the connective planes and produces a secondary involvement of neurophysiological mechanism, appears to fit very closely to the ancient model. It is also compatible with the proposed neurophysiological explanation. Furthermore, it appears to be fruitful also in manual therapy approaches. Drawing on the basis of the “Fascial network hypothesis of meridians”, in which there is an overlap between the channels network described by Traditional Chinese Medicine and the newly-defined fascial system, I propose an intervention through a combination of acupoints that have been selected due to their relationship between “extraordinary acupuncture channels”, the myofascial sequences described by Stecco, and the emotional and adaptive function as contemplated by a psychosomatic model used in posturology. This intervention is aimed at treating both stress and postural imbalance.

The Involvement of Descending Pain Inhibitory System in Electroacupuncture-Induced Analgesia

Chronic pain is a major health problem, which can impair quality of life and reduce productivity. Electroacupuncture (EA), a modality of medicine based on the theories of Traditional Chinese Medicine (TCM), presents great therapeutic effects on chronic pain. Its clinical application has gained increasing popularity, and in parallel, more research has been performed on the mechanisms of EA-induced analgesia. The past decades have seen enormous advances both in neuronal circuitry of needle-insertion and in its molecular mechanism. EA may block pain by activating the descending pain inhibitory system, which originates in the brainstem and terminates at the spinal cord. This review article synthesizes corresponding studies to elucidate how EA alleviate pain via the mediation of this descending system. Much emphasis has been put on the implication of descending serotonergic and noradrenergic pathways in the process of pain modulation. Also, other important transmitters and supraspinal regions related to analgesic effects of EA have been demonstrated. Finally, it should be noticed that there exist some shortcomings involved in the animal experimental designed for EA, which account for conflicting results obtained by different studies.

Cortical Network Response to Acupuncture and the Effect of the Hegu Point: An fNIRS Study

Acupuncture is a practice of treatment based on influencing specific points on the body by inserting needles. According to traditional Chinese medicine, the aim of acupuncture treatment for pain management is to use specific acupoints to relieve excess, activate qi (or vital energy), and improve blood circulation. In this context, the Hegu point is one of the most widely-used acupoints for this purpose, and it has been linked to having an analgesic effect. However, there exists considerable debate as to its scientific validity. In this pilot study, we aim to identify the functional connectivity related to the three main types of acupuncture manipulations and also identify an analgesic effect based on the hemodynamic response as measured by functional near-infrared spectroscopy (fNIRS). The cortical response of eleven healthy subjects was obtained using fNIRS during an acupuncture procedure. A multiscale analysis based on wavelet transform coherence was employed to assess the functional connectivity of corresponding channel pairs within the left and right somatosensory region. The wavelet analysis was focused on the very-low frequency oscillations (VLFO, 0.01–0.08 Hz) and the low frequency oscillations (LFO, 0.08–0.15 Hz). A mixed model analysis of variance was used to appraise statistical differences in the wavelet domain for the different acupuncture stimuli. The hemodynamic response after the acupuncture manipulations exhibited strong activations and distinctive cortical networks in each stimulus. The results of the statistical analysis showed significant differences (p<0.05) between the tasks in both frequency bands. These results suggest the existence of different stimuli-specific cortical networks in both frequency bands and the anaesthetic effect of the Hegu point as measured by fNIRS.

Contralateral Electroacupuncture Relieves Chronic Neuropathic Pain in Rats with Spared Nerve Injury

Background

Acupuncture and electroacupuncture (EA) are widely applied in the treatment of various conditions, including pain. Acupuncture stimulation is applied not only in areas close to pain sites, but also in distal regions or on the contralateral side of the body. Identifying which acupuncture paradigms produce best therapeutic effects is of clinical significance.

Material/Methods

Spared nerve injury (SNI) was applied to establish a rat model of neuropathic pain. We applied 14 sessions of EA (BL 60 and BL 40, 1–2 mA, and 2 Hz, 30 min per session) every other day from days 3 to 29 after surgery on the contralateral or ipsilateral side of pain. von Frey hair was applied to examine mechanical allodynia in the SNI model and analgesic effects of EA. All experimental procedures were approved by the Animal Care and Use Committee of our university, according to the guidelines of the International Association for the Study of Pain.

Results

SNI produced significant and long-lasting mechanical allodynia (p<0.001) in injured paws. Repeated EA on the contralateral side of the pain significantly attenuated mechanical allodynia from 14 days after surgery (p<0.05). By contrast, ipsilateral EA did not show analgesic effects (p>0.05).

Conclusions

These findings indicate that contralateral EA is superior to local EA in some types of pain disorders. Further investigations are needed for a more comprehensive understanding of the central mechanisms of acupuncture.

Histamine H1Receptor Antagonists Facilitate Electroacupuncture Analgesia

This study investigated the influence of the histamine H1receptor antagonists, chlorpheniramine (CHL) and pyrilamine, on the analgesic effects of acupuncture in mice. Nociceptive response was evaluated by the acetic acid-induced abdominal writhe test. Electroacupuncture (EA) at bilateral ST36 reduced the manifestations of acetic acid-induced abdominal writhing, whereas needle insertion without electrostimulation had no such effect. Notably, EA treatment was not associated with any analgesic effects in mice pretreated with naloxone. Low doses of CHL (0.6[Formula: see text]mg/kg; p.o.) or pyrilamine (2.5[Formula: see text]mg/kg; i.p.) as monotherapy did not affect acetic acid-induced abdominal writhing. However, when each agent was combined with EA, acetic acid-induced abdominal writhing was reduced by a greater extent when compared with EA alone. Interestingly, the effects of CHL on acupuncture analgesia were not completely reversed by naloxone treatment. Acetic acid induced increases of phospho-p38 expression in spinal cord, as determined by immunofluorescence staining and Western blot analysis. These effects were attenuated by EA at ST36 and by low doses of histamine H1receptor antagonists, alone or in combination. Our findings show that relatively low doses of histamine H1receptor antagonists facilitate EA analgesia via non-opioid receptors. These results suggest a useful strategy for increasing the efficacy of EA analgesia in a clinical situation.

Modulation of Neurally Mediated Vasodepression and Bradycardia by Electroacupuncture through Opioids in Nucleus Tractus Solitarius

Stimulation of vagal afferent endings with intravenous phenylbiguanide (PBG) causes both bradycardia and vasodepression, simulating neurally mediated syncope. Activation of µ-opioid receptors in the nucleus tractus solitarius (NTS) increases blood pressure. Electroacupuncture (EA) stimulation of somatosensory nerves underneath acupoints P5–6, ST36–37, LI6–7 or G37–39 selectively but differentially modulates sympathoexcitatory responses. We therefore hypothesized that EA-stimulation at P5–6 or ST36–37, but not LI6–7 or G37–39 acupoints, inhibits the bradycardia and vasodepression through a µ-opioid receptor mechanism in the NTS. We observed that stimulation at acupoints P5–6 and ST36–37 overlying the deep somatosensory nerves and LI6–7 and G37–39 overlying cutaneous nerves differentially evoked NTS neural activity in anesthetized and ventilated animals. Thirty-min of EA-stimulation at P5–6 or ST36–37 reduced the depressor and bradycardia responses to PBG while EA at LI6–7 or G37–39 did not. Congruent with the hemodynamic responses, EA at P5–6 and ST36–37, but not at LI6–7 and G37–39, reduced vagally evoked activity of cardiovascular NTS cells. Finally, opioid receptor blockade in the NTS with naloxone or a specific μ-receptor antagonist reversed P5–6 EA-inhibition of the depressor, bradycardia and vagally evoked NTS activity. These data suggest that point specific EA stimulation inhibits PBG-induced vasodepression and bradycardia responses through a μ-opioid mechanism in the NTS.

Enhanced Functional Connectivity between the Bilateral Primary Motor Cortices after Acupuncture at Yanglingquan (GB34) in Right-Hemispheric Subcortical Stroke Patients: A Resting-State fMRI Study

Increasing neuroimaging researches in stroke rehabilitation had revealed the neural mechanisms of rehabilitation therapy. However, little was known about the neural mechanisms of acupuncture therapy in subcortical stroke patients. The aim of this study was to investigate the changes of functional connectivity (FC) between the bilateral primary motor cortices (M1s) after acupuncture intervention in right subcortical stroke patients. Twenty right-hemispheric subcortical stroke patients and 20 healthy subjects were recruited to undergo one functional magnetic resonance imaging (fMRI) scanning. The scanning consisted of resting-state fMRI before and after needling at Yanglinquan (GB34), and task-evoked fMRI. The most significant active point during the left passive thumb-to-index task was chosen as the seed point. The seed-based FC analysis of the bilateral M1s was performed. Stroke patients revealed decreased FC between the bilateral M1s compared with healthy subjects, and the decreased FC was significantly enhanced after acupuncture at GB34. Acupuncture could increase the intrinsically decreased FC between the bilateral M1s which provided further insight into the neural mechanisms of acupuncture for motor function recovery in stroke patients.

Analgesic Neural Circuits Are Activated by Electroacupuncture at Two Sets of Acupoints

To investigate analgesic neural circuits activated by electroacupuncture (EA) at different sets of acupoints in the brain, goats were stimulated by EA at set of Baihui-Santai acupoints or set of Housanli acupoints for 30 min. The pain threshold was measured using the potassium iontophoresis method. The levels of c-Fos were determined with Streptavidin-Biotin Complex immunohistochemistry. The results showed pain threshold induced by EA at set of Baihui-Santai acupoints was 44.74% ± 4.56% higher than that by EA at set of Housanli acupoints (32.64% ± 5.04%). Compared with blank control, EA at two sets of acupoints increased c-Fos expression in the medial septal nucleus (MSN), the arcuate nucleus (ARC), the nucleus amygdala basalis (AB), the lateral habenula nucleus (HL), the ventrolateral periaqueductal grey (vlPAG), the locus coeruleus (LC), the nucleus raphe magnus (NRM), the pituitary gland, and spinal cord dorsal horn (SDH). Compared with EA at set of Housanli points, EA at set of Baihui-Santai points induced increased c-Fos expression in AB but decrease in MSN, the paraventricular nucleus of the hypothalamus, HL, and SDH. It suggests that ARC-PAG-NRM/LC-SDH and the hypothalamus-pituitary may be the common activated neural pathways taking part in EA-induced analgesia at the two sets of acupoints.

The Status of the Quality Control in Acupuncture-Neuroimaging Studies

Using neuroimaging techniques to explore the central mechanism of acupuncture gains increasing attention, but the quality control of acupuncture-neuroimaging study remains to be improved. We searched the PubMed Database during 1995 to 2014. The original English articles with neuroimaging scan performed on human beings were included. The data involved quality control including the author, sample size, characteristics of the participant, neuroimaging technology, and acupuncture intervention were extracted and analyzed. The rigorous inclusion and exclusion criteria are important guaranty for the participants' homogeneity. The standard operation process of acupuncture and the stricter requirement for acupuncturist play significant role in quality control. More attention should be paid to the quality control in future studies to improve the reproducibility and reliability of the acupuncture-neuroimaging studies.

Manipulation Therapy Relieved Pain More Rapidly Than Acupuncture among Lateral Epicondylalgia (Tennis Elbow) Patients: A Randomized Controlled Trial with 8-Week Follow-Up

Radial bone adjustment manipulation treatment may be effective to reduce pain rapidly in lateral epicondylalgia patients and the pathological tension in the biceps brachii muscle is highly concerned. To prove this hypothesis, we conducted a randomized controlled trial and included 35 patients with lateral epicondylalgia for more than 2 months. Either manipulation treatment (n = 16) or acupuncture (n = 19) was given to these patients for 2 weeks and all patients' symptoms were followed up for 8 weeks after treatment. Both groups demonstrated changes in pain VAS score, grip strength, and DASH questionnaire. Lateral epicondylalgia patients who received manipulation treatment felt pain relief sooner than those who had acupuncture treatments during the first few treatments. However, both acupuncture and manipulation are effective, while the difference has no significance at the 8-week follow-up. The trial was registered with Current Controlled Trials ISRCTN81308551 on 5 February 2016.

Verum versus sham manual acupuncture for migraine: a systematic review of randomised controlled trials

BACKGROUND

Manual acupuncture (MA) is commonly used as a treatment for migraine in China. However, its specific clinical effects have been challenged on the basis that some of its effects may relate to psychological or 'placebo' mechanisms.

OBJECTIVE

To identify the effectiveness of verum MA compared with sham acupuncture for the treatment of migraine.

METHODS

Eight electronic databases were searched for randomised controlled trials (RCTs) evaluating the effect of verum versus sham MA on migraine. The quality of included trials was assessed using the 'risk of bias' tool provided by the Cochrane Handbook for Systematic Review of Intervention. RevMan 5.2 software was used for data analysis.

RESULTS

Ten trials with 997 participants were included. Most trials had high methodological quality and were at low risk of bias. Meta-analysis showed superior effects of verum MA over sham acupuncture on the total effective rate, reflected by a reduction in the 'not effective' rate (relative risk (RR) 0.24, 95% CI 0.15 to 0.38; p<0.0001, four trials) and a reduced recurrence rate (RR 0.47, 95% CI 0.28 to 0.81; p=0.006, two trials), but no significant differences in headache intensity, frequency or duration, accompanying symptoms and use of medication. No severe adverse events related to acupuncture occurred during treatment with either verum or sham MA.

CONCLUSIONS

Current clinical evidence suggests that verum acupuncture is superior to sham acupuncture in migraine, reflected by a higher total effective rate and decreased recurrence rate. Nevertheless, further large-scale RCTs with a rigorous design are required to confirm these findings in view of the relative paucity of eligible RCTs and small sample sizes of those included.

Specific Correlation between the Hegu Point (LI4) and the Orofacial Part: Evidence from an fMRI Study

Acupoint specificity is a foundational concept in acupuncture theory. It is closely related to the function of the acupoint. In this study, we sought to probe the central mechanisms of the specific correlation between LI4 and orofacial part in Bell's palsy patients. In total, 36 patients with left Bell's palsy were divided into three groups in random order, and each group received transcutaneous electrical acupoint stimulation (TEAS) at only one of three acupoints (LI4, ST6, and a sham point). A single-block fMRI design paradigm was applied to separately detect neural activity related to different stages of TEAS (prestimulation resting state, stimulation, and poststimulation resting state). Functional magnetic resonance imaging data were acquired during TEAS. There were extensive neuronal activities in the LI4 and ST6 groups and significant differences between stimulation at real and sham points. Brain regions were activated more by real acupoint TEAS than by sham point TEAS. Brain regions that were activated with LI4 and ST6 were broadly overlapping and adjacent. Our results provide supplementary neuroimaging evidence for the existence of acupoint specificity. These results may confirm the central mechanisms of the specific correlation between the Hegu point and the orofacial part.

Brain activation and inhibition after acupuncture at Taichong and Taixi: resting-state functional magnetic resonance imaging

Acupuncture can induce changes in the brain. However, the majority of studies to date have focused on a single acupoint at a time. In the present study, we observed activity changes in the brains of healthy volunteers before and after acupuncture at Taichong (LR3) and Taixi (KI3) using resting-state functional magnetic resonance imaging. Fifteen healthy volunteers underwent resting-state functional magnetic resonance imaging of the brain 15 minutes before acupuncture, then received acupuncture at Taichong and Taixi using the nail-pressing needle insertion method, after which the needle was retained in place for 30 minutes. Fifteen minutes after withdrawal of the needle, the volunteers underwent a further session of resting-state functional magnetic resonance imaging, which revealed that the amplitude of low-frequency fluctuation, a measure of spontaneous neuronal activity, increased mainly in the cerebral occipital lobe and middle occipital gyrus (Brodmann area 18/19), inferior occipital gyrus (Brodmann area 18) and cuneus (Brodmann area 18), but decreased mainly in the gyrus rectus of the frontal lobe (Brodmann area 11), inferior frontal gyrus (Brodmann area 44) and the center of the posterior lobe of the cerebellum. The present findings indicate that acupuncture at Taichong and Taixi specifically promote blood flow and activation in the brain areas related to vision, emotion and cognition, and inhibit brain areas related to emotion, attention, phonological and semantic processing, and memory.

Electroacupuncture stimulation at sub-specific acupoint and non-acupoint induced distinct brain glucose metabolism change in migraineurs: a PET-CT study

BACKGROUND

Acupuncture has analgesic effect to most pain conditions. Many neuroimaging studies were conducted to explore acupoint specificity in pain and other condition, but till now there is still discrepancy. Based on our previous finding, this study investigated the brain metabolism changes of acupuncture analgesia induced by sub-specific acupoint and non-acupoint stimulation.

METHODS

30 migraineurs were included and randomly assigned to 3 groups: Acupuncture Group (AG), Sham Acupuncture Group (SAG) and Migraine Group (MG). In AG, a combination sub-specific points of Shaoyang meridians, Luxi (TE19), San Yangluo (TE8), and Xi Yangguan (GB33) has been stimulated with electroacupuncture, while non-acupoints for SAG were used and MG received no treatment. Positron emission tomography with computed tomography (PET-CT) was used to identify differences in brain glucose metabolism between groups.

RESULTS

In the AG, brain glucose metabolism increase compared with the MG was observed in the middle frontal gyrus, postcentral gyrus, the precuneus, parahippocampus, cerebellum and middle cingulate cortex (MCC), and decrease were observed in the left hemisphere of Middle Temporal Cortex (MTC).In the SAG, compared with MG, glucose metabolism increased in the poster cingulate cortex (PCC), insula, inferior temporal gyrus, MTC, superior temporal gyrus, postcentral gyrus, fusiform, inferior parietal lobe, superior parietal lobe, supramarginal gyrus, middle occipital lobe, angular and precuneus; while, decreased in cerebellum, parahippocampus.

CONCLUSIONS

Acupuncture stimulation at both sub-specific acupoint and non-acupoint yields ameliorating effect to migraine pain, but with evidently differed central mechanism as measured by PET-CT. The pattern of brain glucose metabolism change in acupoint is pertinent and targeted, while in non-acupoint that was disordered and randomized. These finding may provide new perspectives into the validation of acupoint specificity, optimizing acupuncture analgesia and revealing central mechanism of acupuncture analgesia by neuroimaging measurement.

TRIAL REGISTRATION

This trial was registered in the Chinese Clinical Trial Registry, with registration no. ChiCTR-TRC-11001813.

An FMRI study of neuronal specificity in acupuncture: the multiacupoint siguan and its sham point

Clarifying the intrinsic mechanisms of acupuncture's clinical effects has recently been gaining popularity. Here, we choose the Siguan acupoint (a combination of bilateral LI4 and Liv3) and its sham point to evaluate multiacupoint specificity. Thirty-one healthy volunteers were randomly divided into real acupoint (21 subjects) and sham acupoint (10 subjects) groups. Our study used a single block experimental design to avoid the influence of posteffects. Functional magnetic resonance imaging data were acquired during acupuncture stimulation. Results showed extensive increase in neuronal activities with Siguan acupuncture and significant differences between stimulation at real and sham points. Brain regions that were activated more by real acupuncture stimulation than by sham point acupuncture included somatosensory cortex (the superior parietal lobule and postcentral gyrus), limbic-paralimbic system (the calcarine gyrus, precuneus, cingulate cortex, and parahippocampal gyrus), visual-related cortex (the fusiform and occipital gyri), basal ganglia, and the cerebellum. In this way, our study suggests Siguan may elicit specific activities in human brain.

Evidence of timing effects on acupuncture: A functional magnetic resonance imaging study

According to Traditional Chinese Medicine there is an optimum time to administer acupuncture at a particular acupoint. The present study used functional magnetic resonance imaging to investigate the timing effects of acupuncture at the Zusanli (ST36) acupoint. A total of 10 healthy volunteers and 10 post-stroke patients were recruited. The subjects received acupuncture stimulation at ST36 during two time periods: between 7:00 a.m. and 9:00 a.m. (the AM condition) and between 3:00 p.m. and 5:00 p.m. (the PM condition), seven days later. Blood oxygenation level-dependent signals were captured while the patient was receiving the acupuncture stimulation. The results showed a stronger activation in the AM condition than in the PM condition in both healthy and stroke subjects. The significant regions in the healthy subjects included the prefrontal cortex, cingulum, thalamus and cerebellum; for the stroke patients, the significant regions were the cuneus, supplementary motor area and inferior parietal gyrus. Timing can therefore modulate brain activation patterns during acupuncture in healthy subjects and stroke patients; however, the modulation effect appears to differ between the two subject groups. Further studies are required to explore the timing effects of acupuncture at different acupoints in different populations.

Correlation between the Effects of Acupuncture at Taichong (LR3) and Functional Brain Areas: A Resting-State Functional Magnetic Resonance Imaging Study Using True versus Sham Acupuncture

Functional magnetic resonance imaging (fMRI) has been shown to detect the specificity of acupuncture points, as proved by numerous studies. In this study, resting-state fMRI was used to observe brain areas activated by acupuncture at the Taichong (LR3) acupoint. A total of 15 healthy subjects received brain resting-state fMRI before acupuncture and after sham and true acupuncture, respectively, at LR3. Image data processing was performed using Data Processing Assistant for Resting-State fMRI and REST software. The combination of amplitude of low-frequency fluctuation (ALFF) and regional homogeneity (ReHo) was used to analyze the changes in brain function during sham and true acupuncture. Acupuncture at LR3 can specifically activate or deactivate brain areas related to vision, movement, sensation, emotion, and analgesia. The specific alterations in the anterior cingulate gyrus, thalamus, and cerebellar posterior lobe have a crucial effect and provide a valuable reference. Sham acupuncture has a certain effect on psychological processes and does not affect brain areas related to function.

Acupuncture for analgesia in veterinary medicine

Acupuncture for analgesia is growing rapidly in popularity with veterinarians and pet owners. This article summarizes the mechanisms of analgesia derived from acupuncture and reviews current literature on the topic. Areas covered include the local effects at area of needle insertion, systemic effects secondary to circulating neurotransmitters and changes in cell signaling, central nervous system effects including the brain and spinal cord, and myofascial trigger point and pathology treatment. Clinical applications are discussed and suggested in each section. When used by appropriately trained professionals, acupuncture offers a compelling and safe method for pain management in our veterinary patients and should be strongly considered as a part of multimodal pain management plans.

Differential brain effects of laser and needle acupuncture at LR8 using functional MRI

OBJECTIVE

While needle acupuncture is a well-accepted technique, laser acupuncture is being increasingly used in clinical practice. The differential effects of the two techniques are of interest. We examine this in relation to brain effects of activation of LR8, a putative acupuncture point for depression, using functional MRI (fMRI).

METHODS

Sixteen healthy participants were randomised to receive low intensity laser acupuncture to LR8 on one side and needle acupuncture to the contralateral LR8. Stimulation was in an on-off block design and brain patterns were recorded under fMRI.

RESULTS

Significant activation occurred in the left precuneus during laser acupuncture compared with needle acupuncture and significant activation occurred in the left precentral gyrus during needle acupuncture compared with laser acupuncture.

CONCLUSIONS

Laser and needle acupuncture at LR8 in healthy participants produced different brain patterns. Laser acupuncture activated the precuneus relevant to mood in the posterior default mode network while needle acupuncture activated the parietal cortical region associated with the primary motor cortex. Further investigations are warranted to evaluate the clinical relevance of these effects.

Neurobiological mechanisms of acupuncture for some common illnesses: a clinician's perspective

This paper presents some previously proposed neurobiological mechanisms on how acupuncture may work in some clinical applications from a clinician's perspective. For the treatment of musculoskeletal conditions, the proposed mechanisms included microinjury, increased local blood flow, facilitated healing, and analgesia. Acupuncture may trigger a somatic autonomic reflex, thereby affecting the gastric and cardiovascular functions. Acupuncture may also change the levels of neurotransmitters such as serotonin and dopamine, thereby affecting the emotional state and craving. This mechanism may form the basis for the treatment of smoking cessation. By affecting other pain-modulating neurotransmitters such as met-enkephalin and substance P along the nociceptive pathway, acupuncture may relieve headache. Acupuncture may affect the hypothalamus pituitary axis and reduce the release of the luteinizing hormone in the treatment of polycystic ovary syndrome. In addition, two other approaches to the acupuncture mechanism, the fascia connective tissue network and the primo vascular system, are briefly reviewed. Finally, the idea of true versus sham acupuncture points, which are commonly used in clinical trials, is examined because the difference between true and sham points does not exist in the neurobiological model.

Acupuncture Evoked Response in Contralateral Somatosensory Cortex Reflects Peripheral Nerve Pathology of Carpal Tunnel Syndrome

BACKGROUND

Most neuroimaging studies exploring brain response to different acupoints have been performed in healthy adults.

OBJECTIVE

The aim of this study was to compare brain responses to acupuncture at local versus distal acupoints in patients with carpal tunnel syndrome (CTS), who have chronic pain, versus healthy controls (HC) and correlate these responses with median nerve function.

MATERIALS AND METHODS

Brain response to electroacupuncture (EA; 2Hz) was evaluated with event-related functional MRI (fMRI) in patients with CTS (n=37) and age-matched HC (n=30). EA was applied at acupoints local (PC 7 to TW 5) and distal (SP 6 to LV 4) to the CTS lesions.

RESULTS

Brain response in both groups and acupoints included activation of the bilateral secondary somatosensory cortex (S2) and insula, and the contralesional primary somatosensory cortex (cS1). Deactivation was noted in ipsilesional primary somatosensory cortex (S1). A significant difference between local and distal acupoints was found in cS1 for HC, but not CTS. Furthermore, cS1 activation by EA at local acupoints was negatively correlated with median nerve peak sensory latency in HC, but was positively correlated in CTS. No correlation was found for EA at distal acupoints for either group.

CONCLUSIONS

Brain response to EA differs between CTS and HC and, for local acupoint stimulation, is associated with median nerve function, reflecting the peripheral nerve pathophysiology of CTS.

Visualized characterization for cerebral response of acupuncture deqi: paradox underway

Acupuncture as an oriental natural healing therapy with prolonged history has been extensively utilized in the management of great numbers of disorders. Deqi, a renowned acupuncture needling sensation, is profoundly regarded as the predictor and also the prerequisite of a preferable acupuncture treatment efficacy. Till now, there is still no consistency being reached towards the mechanism of acupuncture Deqi as a result of the discrepancy for publicly acknowledged evidence. Recent visualized research on Deqi using modern technologies has demonstrated possible central mechanism towards it. However, there is a conspicuous paradox underway in the research of cerebral response to acupuncture Deqi. This paper provided a view of up-to-date studies using visualized tools to characterize the brain response to acupuncture Deqi, such as functional magnetic resonance imaging (fMRI) and positron emission tomography/computed tomography (PET/CT). The paradox was extruded to highlight certain reasons from a TCM view. It is hypothesized that acupoints located at different dermal sites, state of participant, and needling manipulation can all contribute to the current paradox. Hence, further studies on acupuncture Deqi should pay more attention to the strategy of experiment design with generalized measurement, valid sham control methods, and more to subjects in diseased condition.

FMRI evidence of acupoints specificity in two adjacent acupoints

Objectives. Acupoint specificity is the foundation of acupuncture treatment. The aim of this study is to investigate whether the acupoint specificity exists in two adjacent acupoints. Design and Setting. Two adjacent real acupoints, LR3 (Taichong) and ST44 (Neiting), and a nearby nonacupoint were selected. Thirty-three health volunteers were divided into three groups in random order, and each group only received acupuncture at one of the three points. While they received acupuncture, fMRI scan was performed. Results. The common cerebral activated areas responding to LR3 and ST44 included the contralateral primary somatosensory area (SI) and ipsilateral cerebellum. Acupuncture at LR3 specifically activated contralateral middle occipital gyrus, ipsilateral medial frontal gyrus, superior parietal lobe, middle temporal gyrus, rostral anterior cingulate cortex (rACC), lentiform nucleus, insula, and contralateral thalamus. Stimulation at ST44 selectively activated ipsilateral secondary somatosensory area (SII), contralateral middle frontal gyrus, inferior frontal gyrus, lingual gyrus, lentiform nucleus, and bilateral posterior cingulate cortex (PCC). Conclusions. Acupuncture at adjacent acupoints elicits distinct cerebral activation patterns, and those specific patterns might be involved in the mechanism of the specific therapeutic effects of different acupoints.

Acupuncture point specificity

Acupuncture, as a modality treatment, has gained increasing popularity and acceptance between public and health-care professionals worldwide. Recently, there has been intensive debate about the efficacy of acupuncture therapy due to the conflicting outcome of clinical trials. Acupoint specificity was regarded as one of the core scientific issues with respect to acupuncture practice at the Society for Acupuncture Research international symposium held in 2007. In this chapter, we reviewed the recent development in basic science and clinical studies on the role of acupoint specificity. The evidence cumulated from brain imaging and many biological studies showed that the point specificity in acupuncture does exist, although acupoint specificity-related issues such as sham acupoint and placebo phenomenon need to be seriously considered. How to optimize the efficacy of acupoint and minimize the impact of sham acupuncture is an urgent issue faced by acupuncture community, and more studies are warranted on the subjects.

Acupuncture for chronic pain: individual patient data meta-analysis

BACKGROUND

Although acupuncture is widely used for chronic pain, there remains considerable controversy as to its value. We aimed to determine the effect size of acupuncture for 4 chronic pain conditions: back and neck pain, osteoarthritis, chronic headache, and shoulder pain.

METHODS

We conducted a systematic review to identify randomized controlled trials (RCTs) of acupuncture for chronic pain in which allocation concealment was determined unambiguously to be adequate. Individual patient data meta-analyses were conducted using data from 29 of 31 eligible RCTs, with a total of 17 922 patients analyzed.

RESULTS

In the primary analysis, including all eligible RCTs, acupuncture was superior to both sham and no-acupuncture control for each pain condition (P < .001 for all comparisons). After exclusion of an outlying set of RCTs that strongly favored acupuncture, the effect sizes were similar across pain conditions. Patients receiving acupuncture had less pain, with scores that were 0.23 (95% CI, 0.13-0.33), 0.16 (95% CI, 0.07-0.25), and 0.15 (95% CI, 0.07-0.24) SDs lower than sham controls for back and neck pain, osteoarthritis, and chronic headache, respectively; the effect sizes in comparison to no-acupuncture controls were 0.55 (95% CI, 0.51-0.58), 0.57 (95% CI, 0.50-0.64), and 0.42 (95% CI, 0.37-0.46) SDs. These results were robust to a variety of sensitivity analyses, including those related to publication bias.

CONCLUSIONS

Acupuncture is effective for the treatment of chronic pain and is therefore a reasonable referral option. Significant differences between true and sham acupuncture indicate that acupuncture is more than a placebo. However, these differences are relatively modest, suggesting that factors in addition to the specific effects of needling are important contributors to the therapeutic effects of acupuncture.

Multi-scale order recurrence quantification analysis of EEG signals evoked by manual acupuncture in healthy subjects

To explore the effects of manual acupuncture (MA) on brain activities, we design an experiment that acupuncture at acupoint ST36 of right leg with four different frequencies to obtain electroencephalograph (EEG) signals. Many studies have demonstrated that the complexity of EEG can reflect the states of brain function, so we propose to adopt order recurrence quantification analysis combined with discrete wavelet transform, to analyze the dynamical characteristics of different EEG rhythms under acupuncture, further to explore the effects of MA on the complexity of brain activities from multi-scale point of view. By analyzing the complexity of five EEG rhythms, it is found that the complexity of delta rhythm during acupuncture is lower than before acupuncture, and for alpha rhythm that is higher, but for beta, theta and gamma rhythms there are no obvious changes. All of those effects are especially obvious during acupuncture with frequency of 200 times/min. Furthermore, the determinism extracted from delta, alpha and gamma rhythms can be regarded as a characteristic parameter to distinguish the state acupuncture at 200 times/min and the state before acupuncture. These results can provide a theoretical support for selecting appropriate acupuncture frequency for patients in clinical, and the proposed methods have the potential of exploring the effects of acupuncture on brain activities.

Haemodynamic changes in the superior mesenteric artery induced by acupuncture stimulation on the lower limbs

Acupuncture is commonly performed on acupoints. A comparison of quantitative physiological alterations induced by stimulation on different acupoints has never been performed in the superior mesenteric artery (SMA) in humans. Therefore, we investigated changes in blood flow volume (BFV) in the SMA as an indicator of physiological effects induced by stimulation on 3 points. Thirty healthy participants aged 29 ± 10 years (mean ± SD) were enrolled. All participants underwent stimulations on 3 points located in the lower legs: ST36, LR3, and a non-acupoint. Control pertains to a condition with no-stimulation. Stimulation was performed bilaterally with manual rotation of the needles. BFV was measured by ultrasonography before insertion and 10, 20, 30, and 60 minutes after stimulation. Following acupuncture on ST36, BFV increased significantly 20 and 30 minutes after stimulation, compared to BFV before insertion (P < 0.05). Following stimulation on LR3 and the non-acupoint, no significant differences in BFV could be found. Relative to the no-stimulation group, stimulation on LR3, and the non-acupoint, stimulation on ST36 elicited a significant increase in BFV (P < 0.05). The results suggest that stimulation on the different points causes distinct physiological effects in BFV in the SMA.

Investigation of the delayed neuronal effects of acupuncture manipulations

OBJECTIVES

The aim of this study was to investigate the delayed neuronal effects of acupuncture manipulations by observing blood oxygen level-dependent (BOLD) signal intensities.

SUBJECTS

Fifteen (15) healthy, acupuncture-naive, right-handed subjects (all males; mean age, 23 years; range, 21-24 years) participated in this study.

DESIGN AND INTERVENTIONS

Each subject was scanned in eight sessions that consisted of two repeated baseline scans (Period 1), two repeated scans with acupuncture stimulation at right LR2 (Period 2), two repeated scans with retention (Period 3), and two repeated scans after removal of the needle (Period 4).

OUTCOME MEASURES

Sixteen (16) regions of interest (ROI) were defined. The BOLD signals for each session were obtained for each ROI. A mixed-effects analysis of variance (ANOVA) test was performed in order to investigate the BOLD signal differences of the Periods in the 16 ROIs.

RESULTS

The BOLD signal intensities increased in Periods 2 and 3, and then started to decrease in Period 4 in the right amygdala, supramarginal gyrus, temporal pole, and superior temporal gyrus. However, the BOLD signal intensity in Period 4 was significantly higher than that of Period 1. Especially, BOLD signal intensity was elevated promptly in the insula and the parahippocampal gyrus, whereas it was persistently elevated (delayed effect) in the amygdala.

CONCLUSIONS

BOLD signals were persistently elevated for at least 8 minutes after removal of the acupuncture needle or for at least 19 minutes after rotation of an acupuncture needle in some specific brain areas previously linked with LR2. In those specific brain ROIs, neuronal activation accompanying and following acupuncture showed both prompt and delayed effects.