Electroacupuncture at Hoku elicits dual effect on autonomic nervous system in anesthetized rats

Efficacy and safety of distal radial approach for cardiac catheterization: A systematic review and meta-analysis

BACKGROUND

The traditional radial approach (RA) is recommended as the standard method for coronary angiography (CAG), while a distal RA (DRA) has been recently used for CAG.

AIM

To assess the efficacy and safety of the DRA vs RA during CAG.

METHODS

The following databases were searched through December 2020: MEDLINE, the Cochrane Central Register of Controlled Trials, EMBASE, the World Health Organization International Clinical Trials Platform Search Portal, and ClinicalTrials.gov. Individual randomized-controlled trials for adult patients undergoing cardiac catheterization were included. The primary outcomes were the successful cannulation rate and the incidence of radial artery spasm (RAS) and radial artery occlusion (RAO). Study selection, data abstraction and quality assessment were independently performed using the Grading of Recommendations, Assessment, Development, and Evaluation approach.

RESULTS

Three randomized control trials and 13 registered trials were identified. The two approaches showed similar successful cannulation rates [risk ratio (RR) 0.90, 95% confidence interval (CI): 0.72-1.13]. The DRA did not decrease RAS (RR 0.43, 95%CI: 0.08-2.49) and RAO (RR 0.48, 95%CI: 0.18-1.29). Patients with the DRA had a shorter hemostasis time in comparison to those with the RA (mean difference -6.64, 95%CI: -10.37 to -2.90). The evidence of certainty was low.

CONCLUSION

For CAG, the DRA would be safer than the RA with comparable cannulation rates. Given the limited data, additional research, including studies with standard protocols, is necessary.

The role of toll-like receptor 4 and mast cell in the ameliorating effect of electroacupuncture on visceral hypersensitivity in rats

BACKGROUND

Visceral hypersensitivity is one of the main pathogenesis of irritable bowel syndrome (IBS) and mast cell activation is closely related to visceral hypersensitivity. As a critical molecule of the innate immune system, toll-like receptor 4 (TLR4) may modulate the activation of mast cell. Alleviating effect of electroacupuncture (EA) on visceral hypersensitivity has been proved, whereas, whether the TLR4 and mast cell is involved in this process remains unclear.

METHODS

Forty Sprague-Dawley rats were randomly divided into five groups: control group, model group, EA group, sham EA group, and mast cell stabilizer (MCS) group. Visceral sensitivity during colorectal distension was assessed by the measurement of visceral motor reflex (VMR). TLR4 mRNA and protein expression were assessed by real-time PCR and immunohistochemistry, respectively. Mast cell number and mast cell tryptase (MCT) expression were detected. The level of inflammatory cytokine in serum was detected with ELISA.

KEY RESULTS

Visceral sensitivity was significantly higher in the model group than in the control group. EA and MCS significantly reduced VMR score at 0.8 mL and 1.2 mL distention pressures. Compared with model group, TLR4 mRNA expression, the protein expression of TLR4 and MCT, and the number of mast cells with degranulation in the colonic tissue, serum concentration of IL-1β and IL-8 were all significantly decreased in EA and MCS group.

CONCLUSIONS & INFERENCES

Electroacupuncture ameliorated visceral hypersensitivity in colon-sensitized model probably via decreasing the level of pro-inflammatory cytokines released by mast cell which were decreased when the TLR4 expression in the colonic tissue was downregulated by EA.

Acupuncture for Infantile Colic: A Systematic Review of Randomised Controlled Trials

INTRODUCTION

Infantile colic is a common condition causing considerable deterioration in the quality of life of both infants and their parents. Minimal acupuncture, a gentle needling technique without strong muscle stimulation, has primarily been used to treat this condition, but the clinical evidence of its efficacy and safety is yet to be established. The objective of this review was to assess clinical evidence of the safety and efficacy of acupuncture for infantile colic.

METHODS

To identify studies for inclusion, PubMed, Cochrane Library, Google Scholar, China Knowledge Resource Integrated Database, Wanfang, and Oriental Medicine Advanced Searching Integrated System were searched until January 2017. Only randomised controlled trials of infantile colic in patients aged 0 to 25 weeks, who were treated with acupuncture, were included. To assess the quality, the risk of bias was determined for each study by two authors. The intention was to perform a meta-analysis, but this was not possible in this study due to considerable clinical heterogeneity among the included studies.

RESULTS

Of the 601 studies identified, only four randomized controlled trials were included in this review. All included studies were conducted in northern European countries. Most studies showed a low risk of bias in most domains. Minimal acupuncture on LI4 or ST36 without strong stimulation was used in all studies. From the narrative analysis, acupuncture appears to be effective in alleviating the symptoms of colic, including crying and feeding and stooling problems, and may have only minor adverse effects. However, clinical evidence could not be confirmed owing to considerable clinical heterogeneity and the small sample sizes of the included studies.

CONCLUSION

There is currently no conclusive evidence on the safety and efficacy of acupuncture for infantile colic. Rigorous full-scale randomized controlled trials will be necessary in future.

Infant colic: mechanisms and management

Infant colic is a commonly reported phenomenon of excessive crying in infancy with an enigmatic and distressing character. Despite its frequent occurrence, little agreement has been reached on the definition, pathogenesis or the optimal management strategy for infant colic. This Review aims to delineate the definitional entanglement with the Rome IV criteria, which were published in 2016, as the leading, most recent diagnostic criteria. Moreover, neurogenic, gastrointestinal, microbial and psychosocial factors that might contribute to the pathophysiology of infant colic are explored. This Review underlines that a comprehensive medical history and physical examination in the absence of alarm symptoms serve as guidance for the clinician to a positive diagnosis. It also highlights that an important aspect of the management of infant colic is parental education and reassurance. Management strategies, including behavioural, dietary, pharmacological and alternative interventions, are also discussed. Owing to a lack of large, high-quality randomized controlled trials, none of these therapies are strongly recommended. Finally, the behavioural and somatic sequelae of infant colic into childhood are summarized.

Investigation of Interactive Activity of Electro-Acupuncture on Pharmacokinetics of Sildenafil and Their Synergistic Effect on Penile Blood Flow in Rats

Erectile dysfunction (ED) is a disorder found in males throughout the world, which negatively affects relationships with partners with advancing age. Hence, in this study, we tested a combined novel treatment of electro-acupuncture (EA) and sildenafil citrate against ED. In addition to EA therapy, the sildenafil citrate, a phosphodiesterase 5 inhibitor, is a widely recognized drug that has achieved considerable success in the treatment of ED. However, the combined effect of both the EA and sildenafil has not yet been investigated. Hence, we aimed to examine the effect of EA on the pharmacokinetics and pharmacodynamics of sildenafil in rat plasma. The pharmacokinetic parameters were determined using ultra performance liquid chromatography (UPLC) after EA and sildenafil administration (10 mg/Kg). Following this, the pharmacodynamics was studied via blood flow pattern using developing Doppler images of the lower body and penis. The pharmacokinetic studies demonstrated that sildenafil significantly increases by administration of low-frequency EA. Further, the pharmacodynamic studies using Doppler imaging revealed an elevated blood flow in rat penis compared with lower body during combined treatment of sildenafil and low-frequency EA. These data indicate a synergistic therapeutic effect of EA and sildenafil for the treatment of ED.

The Influence of Electro-Acupuncture Stimulation to Female Constipation Patients

This study aims to examine electro-acupuncture stimulation (EA) assisted therapy with analysis of heart rate variability to understand autonomic nervous activity variability (ANAV) and to track the changes in female patients with constipation. The average ages were 42±12 years old. The participants were divided by a single-blind and randomized trial into two groups: the electro-acupuncture-point group, and the non-electro-acupuncture-point group. Both of the groups had eight treatments, once a week. For the electro-acupuncture (EA) group, needles were inserted into their Zusunli (ST36), Shangiuxu (ST37), Tiensu (ST25), Shueidao (ST28), Guanyuan (CV4) and Qihai (CV6) points. For the sham electro-acupuncture (SA) group, needles were inserted into acu-points that were not the ones mentioned for the EA group. While inserting needles, needles were inserted lightly into the participants' skin and removed quickly (mock Transcutaneous Electrical Nerve Stimulation, TENTS). After an eight-week treatment period, the autonomic nervous system activities of the SA group did not show significant differences in their heart rate variability. However, the autonomic nervous system activities of the EA group had continuously increased after each session. The normalized high frequency powers (nHFP) of their autonomic nervous system activities were 26.79 in the first week, and they increased to 32.28 in the fourth week. In the eighth week, their nHFP had increased to 37.60 (p < 0.05). The normalized low frequency power (nLFP) was 30.81 in the first week. However, it decreased to 25.98 after three weeks of treatment. After the eight-week treatment period, the nLFP decreased to 24.84 (p < 0.05). After the eight-week treatment, the control group did not appear to undergo any physiological change, while the constipation had been improved for the experimental group. It was found that the activation of parasympathetic nervous system in the experimental group increased after the eight-week treatment. The effects of such a result on the enhancement of the activation of parasympathetic nervous system and the improvement of constipation should be further discussed.

Comparison of electroacupuncture frequency-related effects on heart rate variability in healthy volunteers: a randomized clinical trial

This study aimed to compare the effects of high frequency electroacupuncture (EA) and low-frequency EA on the autonomic nervous system by using a heart rate variability measuring device in normal individuals. Fourteen participants were recruited and each participated in the high-frequency and low-frequency sessions (crossover design). The order of sessions was randomized and the interval between the two sessions was over 2 weeks. Participants received needle insertion with 120-Hz stimulation during the high-frequency session (high-frequency EA group), and with 2-Hz stimulation during the low-frequency session (low-frequency EA group). Acupuncture needles were directly inserted perpendicularly to LI 4 and LI 11 acupoints followed by delivery of electric pulses to these points for 15 minutes. Heart rate variability was measured 5 minutes before and after EA stimulation by a heart rate variability measuring system. We found a significant increase in the standard deviation of the normal-to-normal interval in the high-frequency EA group, with no change in the low-frequency EA group. Both the high-frequency and low-frequency EA groups showed no significant differences in other parameters including high-frequency power, low-frequency power, and the ratio of low-frequency power to high-frequency power. Based on these findings, we concluded that high-frequency EA stimulation is more effective than low-frequency EA stimulation in increasing autonomic nervous activity and there is no difference between the two EA frequencies in enhancing sympathovagal balance.

Gastrointestinal symptoms of infantile colic and their change after light needling of acupuncture: a case series study of 913 infants

BACKGROUND

Infantile colic is a common painful clinical condition associated with signs of distended intestines and an increase in colon peristalsis. However, clinical documentation of observed gastrointestinal functions in the condition is still lacking. Even though the ailment is common, no clear treatment guidelines exist. While acupuncture with minimal stimulation has been shown to be effective in reducing crying behaviour of infants suffering from colic, the documented effect of acupuncture on gastrointestinal function in children with infantile colic is scarce. This case series study aims to document the symptoms of routinely rated gastrointestinal function and the changes in these symptoms after minimal acupuncture in a larger group of children with infantile colic.

METHODS

This study included 913 infants with normal weights, and lengths at birth. The infants' mean age was 5.4 weeks when the observations started, and had colic symptoms since two weeks after birth. Light needling stimulation of the acupuncture point LI4 was performed for 10-20 seconds bilaterally on a daily basis for a mean of 6.2 consecutive days. A questionnaire with verbal rating scales for the parents' evaluation was used before and after the treatment period.

RESULTS

Before treatment the infants were assessed by the parents in terms of 'often have inflated stomachs' (99%) and 'seldom drool' (76%), 'regurgitate' (53%) and 'belch' (62%). Moreover, the reported frequency of defecation was 5-8 times per day (64%), with a yellowish-green colour (61%) and with a water-thin consistency (74%). After treatment, the variables of inflated stomachs, drooling and regurgitating were systematically changed, and rated by the parents as occurring 'sometimes' while belching was rated as occurring 'often' and the frequency of defecation was reduced to 1-4 times/day with a mustard yellow colour and a gruel-like consistency. The parents also rated their impression of the infants' general colic symptoms including crying behaviour as much ameliorated in 76% of the cases.

CONCLUSION

The results of the present study show that minimal acupuncture at LI4 in infantile colic is an effective and easy treatment procedure that, furthermore, is reported to be without serious side effects.

Effect of electroacupuncture at Tsusanli on intestinal myoelectric activity in rats with incomplete intestinal obstruction

AIM: To investigate the effect of electroacupuncture at Tsusanli on the regulation of gastrointestinal motility in rats with incomplete intestinal obstruction.

METHODS: The 1/2 terminal ileum of rats with intestinal obstruction was ligated to generate a model of incomplete intestinal obstruction. Rats were randomly divided into control group (n = 10), sham-operated group (n = 10), intestinal obstruction group (IO group, n = 10), and intestinal obstruction + electroacupuncture group (14 d IO + EA subgroup, n = 10, 21 d IO + EA subgroup, n = 10). At 2 hours after the last treatment, changes in body weight and myoelectric slow wave activity in the ileum were recorded, and ileal histomorphological changes were observed with the unaided eyes.

RESULTS: Compared to the control group, rats of the IO group showed significant weight loss (P < 0.01). However, the body weight increased obviously in the IO+EA group compared to the IO group (P < 0.01). The amplitude (mV) for the myoelectric slow wave in the IO group on day 14 was significantly lower than that in the control group (0.11 ± 0.03 vs 0.35 ± 0.06, P < 0.01), and the coefficient of variation (CV) of the mean frequency (%) and amplitude (%) was significantly higher in the IO group than in the control and sham-operated groups (27.71 ± 10.54 vs 14.08 ± 4.22, 22.00 ± 6.24; 75.54 ± 8.59 vs 15.84 ± 1.49, 20.67 ± 7.57, all P < 0.01). After 14 days of electroacupuncture, the mean frequency for the myoelectric slow wave in the ileum in the IO + EA group was significantly higher than that in the IO group (33.18 ± 2.56 vs 24.01 ± 0.92, P < 0.01). Compared to the IO group, the mean amplitude (mV) in the IO + EA group remarkably increased on day 5 (0.25 ± 0.09 vs 0.11 ± 0.03, P < 0.05). The CV of frequency (%) in the IO + EA group was significantly lower than that in the IO group (17.02 ± 3.62 vs 27.71 ± 10.54, P < 0.05). The CV of amplitude (%) in the IO + EA group was significantly lower than that in the IO group (58.39 ± 9.56 vs 75.54 ± 8.59, P < 0.01). After 21 days of electroacupuncture, the mean frequency in the ileum in the IO + EA group significantly increased compared to the IO group (40.55 ± 5.29 vs 33.18 ± 2.56, P < 0.01). Compared to the IO group, the CV of amplitude (%) in the IO + EA group was significantly lower (44.00 ± 11.61 vs 58.39 ± 9.56, P < 0.05).

CONCLUSION: A rat model of incomplete intestinal obstruction could be generated by ligating the 1/2 terminal ileum of rats with intestinal obstruction. Electroacupuncture at Tsusanli exerts a therapeutic effect against incomplete intestinal obstruction by regulating intestinal myoelectric activity.

Acupuncture reduces crying in infants with infantile colic: a randomised, controlled, blind clinical study

OBJECTIVE

To investigate whether acupuncture reduces the duration and intensity of crying in infants with colic. Patients and methods 90 otherwise healthy infants, 2-8 weeks old, with infantile colic were randomised in this controlled blind study. 81 completed a structured programme consisting of six visits during 3 weeks to an acupuncture clinic in Sweden. Parents blinded to the allocation of their children met a blinded nurse. The infant was subsequently given to another nurse in a separate room, who handled all infants similarly except that infants allocated to receive acupuncture were given minimal, standardised acupuncture for 2 s in LI4.

RESULTS

There was a difference (p=0.034) favouring the acupuncture group in the time which passed from inclusion until the infant no longer met the criteria for colic. The duration of fussing was lower in the acupuncture group the first (74 vs 129 min; p=0.029) and second week (71 vs 102 min; p=0.047) as well as the duration of colicky crying in the second intervention week (9 vs 13 min; p=0.046) was lower in the acupuncture group. The total duration of fussing, crying and colicky crying (TC) was lower in the acupuncture group during the first (193 vs 225 min; p=0.025) and the second intervention week (164 vs 188 min; p=0.016). The relative difference from baseline throughout the intervention weeks showed differences between groups for fussing in the first week (22 vs 6 min; p=0.028), for colicky crying in the second week (92 vs 73 min; p=0.041) and for TC in the second week (44 vs 29 min; p=0.024), demonstrating favour towards the acupuncture group.

CONCLUSIONS

Minimal acupuncture shortened the duration and reduced the intensity of crying in infants with colic. Further research using different acupuncture points, needle techniques and intervals between treatments is required.

Acupuncture: is it effective for treatment of insulin resistance?

Insulin resistance (IR) is closely associated with obesity, type 2 diabetes mellitus (T2DM), hypertension, polycystic ovary syndrome (PCOS), non-alcohol fatty liver diseases (NAFLD) and metabolic syndrome and is also a risk factor for serious diseases such as cardiovascular diseases. Pharmacological treatments available for IR are limited by drug adverse effects. Because acupuncture has been practiced for thousands of years in China, it has been increasingly used worldwide for IR-related diseases. This review analyses 234 English publications listed on the PubMed database between 1979 and 2009 on the effectiveness of acupuncture as a treatment for IR. These publications provide clinical evidence, although limited, in support of the effectiveness of acupuncture in IR. At this stage, well-designed, evidence-based clinical randomized controlled trial studies are therefore needed to confirm the effects of acupuncture on IR. Numerous experimental studies have demonstrated that acupuncture can correct various metabolic disorders such as hyperglycemia, overweight, hyperphagia, hyperlipidemia, inflammation, altered activity of the sympathetic nervous system and insulin signal defect, all of which contribute to the development of IR. In addition, acupuncture has the potential to improve insulin sensitivity. The evidence has revealed the mechanisms responsible for the beneficial effects of acupuncture, though further investigations are warranted.

Effects of Minimal Acupuncture in Children with Infantile Colic – a Prospective, Quasi-Randomised Single Blind Controlled Trial

Background

Colic causes crying in 10–30% of infants and is one of the primary reasons parents seek health care. Treatments are generally not totally effective and some cause side effects. In this study we aimed to test the effect of light needling (minimal acupuncture) on crying.

Methods

Forty children (median six weeks of age) with excessive crying unresponsive to conventional therapies, were recruited from 21 Child Welfare Clinics within an area of western Sweden, and quasi-randomised to control or light needling treatment. Parents were unaware of which group their child was assigned to. Children were given light needling acupuncture on one point (LI4) on both hands for approximately 20 seconds on four occasions, or received the same care except needling. Parental assessment questionnaires were used pre- and post-treatment to assess crying intensity, frequency, duration of crying and pain related behaviour throughout the day in six hour periods.

Results

Light needling resulted in a significant reduction in the rated crying intensity (assessed by a numeric rating scale, 0 to 10). For example, during the morning time period 0600–1200 hours, the median (range) rated crying intensity changed from 6 (1 to 9) pre-treatment to 2 (0 to 5) post-treatment (P=0.002), in the light needling group. The corresponding ratings for the children in the control group was 6 (0 to 10) and 5 (0 to 10) respectively. The difference between the groups was significant (P=0.016). There were also significant differences between the groups for the afternoon (1200–1800 hours), and evening (1800–midnight) time periods. Pain related behaviour like facial expression, was also significantly less pronounced in the light needling group as compared to the control group post-treatment, (P=0.027). The parents rated the light needling as more effective in improving symptoms than the control group (P<0.001).

Conclusion

Four treatments with light needling on one point in the hand may alleviate crying and pain related behaviour without any noted side effects.

The effect of 2 Hz and 100 Hz electrical stimulation of acupoint on ankle sprain in rats

The electrical stimulation of acupoint (ESA) releases several endogenous neuropeptides, which play important roles in management of pain and inflammation. ESA with low and high frequencies has been shown to release different neuropepides, suggesting its various therapeutic effects. Pain and edema are major problems for ankle sprain. However, there have been few reports on the effects of ESA for ankle sprain. We aimed to investigate that ESA can reduce pain and edema resulting from ankle sprain, and whether there is a difference in therapeutic effects between low and high frequency ESA. To induce ankle sprain in Sprague-Dawley rats, the ankle of right hindpaw was overextended in direction of simultaneous inversion and plantar flexion. Stepping force and edema in the paw of the sprained ankle were measured by electronic balance and plethysmometer, respectively. In both 2 and 100 Hz ESA groups, stepping force was increased significantly in similar degrees (p<0.05). Only 2 Hz ESA produced the significant rapid decrease in ankle edema. This study demonstrates that ESA of 2 Hz and 100 Hz shows comparable analgesic effects, but only 2 Hz ESA can facilitate the reduction of edema caused by ankle sprain.

Review article: therapeutic roles of acupuncture in functional gastrointestinal disorders

Acupuncture has been practiced empirically in China for several millennia, and is being increasingly accepted by practitioners and patients worldwide. Functional gastrointestinal disorders are common in clinical gastroenterology. The prevalence of one or more functional gastrointestinal disorders is estimated to be as high as 70% in general population using Rome diagnostic criteria. Since functional gastrointestinal disorders are diagnosed based on symptoms and the exact aetiologies for most of functional gastrointestinal disorders are not completely known, it is not unusual that the treatment for these disorders is unsatisfactory and alternative therapies are attractive to both patients and practitioners. During the latest decades, a considerable number of studies have been performed on acupuncture for the treatment of functional gastrointestinal disorders and underlying mechanisms. In this article, we reviewed available data in the literature on the applications and mechanisms of acupuncture for the treatment of functional gastrointestinal disorders, including functional oesophageal disorders, nausea and vomiting, functional dyspepsia, irritable bowel syndrome, constipation, etc. A summary is provided based on the quality and quantity of published studies regarding the efficacy of acupuncture in treating these various disorders. In addition, the methodology of acupuncture is also introduced.

Tetanization-induced pelvic-to-pudendal reflex plasticity in anesthetized rats

Reflex plasticity between pelvic afferent and pudendal efferent nerve fibers was examined in anesthetized rats. Brief high-frequency electric stimulation (300 pulses at 100 Hz) of the pelvic nerve afferent fiber produced a long-lasting potentiation of the pelvic-to-pudendal reflex (PPR). This tetanization-induced potentiation was abolished by a selective N-methyl-D-aspartate (NMDA) receptor antagonist and attenuated by a non-NMDA excitatory amino acid receptor antagonist. However, the GABA(A)-receptor antagonist had no effect on this potentiation. Both intrathecal glutamate (0.1 mM, 2-5 microl it) and NMDA (0.1 mM, 2-5 microl it) induced a potentiation of PPR similar to that of tetanization. Agonist-induced potentiation was shorter than tetanization-induced potentiation. The duration of the contraction wave of intraurethral pressure, elicited by PPR, was elongated by tetanization-induced potentiation, whereas the peak pressure was not affected. All these results demonstrate that brief high-frequency stimulation of the pelvic nerve afferent fiber can induce a distinct and long-lasting modulation in PPR activity and this change may be involved in nociceptive C afferent-induced obstructive urinary dysfunctions.

Ovarian blood flow responses to electro-acupuncture stimulation at different frequencies and intensities in anaesthetized rats

The purpose of the present study was to investigate changes in ovarian blood flow (OBF) in response to electro-acupuncture (EA) stimulation at different frequencies and intensities in anaesthetized rats. Whether the ovarian sympathetic nerves were involved in OBF responses was elucidated by severance of the ovarian sympathetic nerves. In addition, how changes in the systemic circulation affected OBF was evaluated by continuously recording blood pressure. OBF was measured on the surface of the left ovary using laser Doppler flowmeter. Acupuncture needles with a diameter of 0.3 mm were inserted bilaterally into the abdominal and the hindlimb muscles and connected to an electrical stimulator. Two frequencies-2 Hz (low) and 80 Hz (high)-with three different intensities-1.5, 3, and 6 mA-were applied for 35 s. Both low- and high-frequency EA at 1.5 mA and high-frequency EA at 3 mA had no effect on OBF or mean arterial blood pressure (MAP). Low-frequency EA at 3 and 6 mA elicited significant increases in OBF. In contrast, high-frequency EA with an intensity of 6 mA evoked significant decreases in OBF, followed by decreases in MAP. After severance of the ovarian sympathetic nerves, the increases in the OBF responses to low-frequency EA at 3 and 6 mA were totally abolished, and the responses at 6 mA showed a tendency to decrease, probably because of concomitant decreases in MAP. The decreased OBF and MAP responses to high-frequency EA at 6 mA remained after the ovarian sympathectomy, and the difference in the responses before and after ovarian sympathectomy was nonsignificant. In conclusion, the present study showed that low-frequency EA stimulation increases OBF as a reflex response via the ovarian sympathetic nerves, whereas high-frequency EA stimulation decreases OBF as a passive response following systemic circulatory changes.

Depressor effect on blood pressure and flow elicited by electroacupuncture in normal subjects

To clarify the effect of electroacupuncture (Ea) on the activity of the cardiovascular system in normal individuals, hemodynamic parameters including arterial blood pressure (BP), finger blood flow (FBF) and heart rate (HR) as well as paravertebral temperature (PVT) were non-invasively recorded under Ea stimulation. Surface stimulation electrode was placed on the Hoku point (Li-4). Square wave pulses (0.05 ms) were applied from a stimulator with a stimulation frequency of 2 Hz (3 min). The stimulation intensity was five times of sensory threshold. BP and FBF were decreased (68.5+/-6.0%, P<0.01 and 96.8+/-1.1%, P<0.01 of control, respectively, n=7) while HR and PVT were increased significantly (115.0+/-5.1 of control, P<0.05 and 0.054+/-0.004 degree C, P<0.01, respectively, n=7) during Ea treatment. The results suggested an inhibition in sympathetic outflow, which induced vasodilatation of systemic arteriole and decrease in BP and FBF were elicited by Ea stimulation.

Pressor effect on blood pressure and renal nerve activity elicited by electroacupuncture in intact and acute hemorrhage rats

The neural mechanism underlying the effect of electroacupuncture (Ea) on arterial blood pressure (BP) and renal nerve activity (RNA) in the intact state and during acute hemorrhage was investigated in anesthetized rats. Two acupoints, Hoku (Li-4, at the junction of the first and the second metacarpal bone) and Tsusanli (St-36, at the lateral upper tibia bone), were tested using Ea of two different frequencies (2 and 20 Hz). In the intact state, Ea at Hoku elicited an elevation of BP in parallel with RNA, while Ea found no response with identical parameters at Tsusanli. The pattern of the pressor response caused by a low frequency Ea (2 Hz) at Hoku was different than a high frequency one (20 Hz), i.e. a tonic effect was elicited with 2 Hz, while a phasic one was induced with 20 Hz. In mild hemorrhage conditions (10% of BP decrease), similar pressor effects, as in intact rats, were also elicited by Ea. However, in severe hemorrhage conditions (20 and 30% BP decrease), Ea induced a pressor effect on RNA and an attenuated effect on BP. BP and RNA showed a significant correlation in intact and mild hemorrhage conditions, but not in severe hemorrhage conditions. All the results suggested that Ea at Hoku with appropriate stimulation parameters can increase and maintain BP in normal and hemorrhage conditions, and such a therapeutic technique has potential in clinical practice.