Electrical impedance along connective tissue planes associated with acupuncture meridians
Andrew C Ahn, Junru Wu, Gary J Badger, Richard Hammerschlag, Helene M Langevin, Andrew C Ahn, Junru Wu, Gary J Badger, Richard Hammerschlag, Helene M Langevin
Abstract
Background: Acupuncture points and meridians are commonly believed to possess unique electrical properties. The experimental support for this claim is limited given the technical and methodological shortcomings of prior studies. Recent studies indicate a correspondence between acupuncture meridians and connective tissue planes. We hypothesized that segments of acupuncture meridians that are associated with loose connective tissue planes (between muscles or between muscle and bone) visible by ultrasound have greater electrical conductance (less electrical impedance) than non-meridian, parallel control segments.
Methods: We used a four-electrode method to measure the electrical impedance along segments of the Pericardium and Spleen meridians and corresponding parallel control segments in 23 human subjects. Meridian segments were determined by palpation and proportional measurements. Connective tissue planes underlying those segments were imaged with an ultrasound scanner. Along each meridian segment, four gold-plated needles were inserted along a straight line and used as electrodes. A parallel series of four control needles were placed 0.8 cm medial to the meridian needles. For each set of four needles, a 3.3 kHz alternating (AC) constant amplitude current was introduced at three different amplitudes (20, 40, and 80 microAmps) to the outer two needles, while the voltage was measured between the inner two needles. Tissue impedance between the two inner needles was calculated based on Ohm's law (ratio of voltage to current intensity).
Results: At the Pericardium location, mean tissue impedance was significantly lower at meridian segments (70.4 +/- 5.7 Omega) compared with control segments (75.0 +/- 5.9 Omega) (p = 0.0003). At the Spleen location, mean impedance for meridian (67.8 +/- 6.8 Omega) and control segments (68.5 +/- 7.5 Omega) were not significantly different (p = 0.70).
Conclusion: Tissue impedance was on average lower along the Pericardium meridian, but not along the Spleen meridian, compared with their respective controls. Ultrasound imaging of meridian and control segments suggested that contact of the needle with connective tissue may explain the decrease in electrical impedance noted at the Pericardium meridian. Further studies are needed to determine whether tissue impedance is lower in (1) connective tissue in general compared with muscle and (2) meridian-associated vs. non meridian-associated connective tissue.
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References
- Chen KG. Electrical properties of meridians. IEEE Eng Med Biol Mag. 1996;15:58–63. doi: 10.1109/51.499759.
- Hyvarinen J, Karlsson M. Low-resistance skin points that may coincide with acupuncture loci. Med Biol. 1977;55:88–94.
- Nakatani Y, Yamashita K. Ryodoraku Acupuncture. Tokyo, Ryodoraku Research Institute; 1977.
- Nakatani Y. Skin electric resistance and ryodoraku. J Autonomic Nerve. 1956;6
- Niboyet J. Nouvelle constatations sur les proprietes electriques des ponts Chinois. Bull Soc Acup. 1958;30
- Reichmanis M, Marino AA, Becker RO. DC skin conductance variation at acupuncture loci. Am J Chin Med. 1976;4:69–72. doi: 10.1142/S0192415X7600010X.
- Reichmanis M, Marino AA, Becker RO. Electrical correlates of acupuncture points. IEEE Trans Biomed Eng. 1975;22:533–535.
- Becker RO, Reichmanis M, Marino AA, Spadaro JA. Electrophysiological correlates of acupuncture points and meridians. Psychoenergetic Systems. 1976;1:105–112.
- Becker RO, Selden G. The body electric : electromagnetism and the foundation of life. 1st. New York, Morrow; 1985. p. 364 p..
- Terral C, Rabischong P. A scientific basis for acupuncture? The Journal of Alternative and Complementary Medicine. 1997;3:S–55-S-65.
- Voll R. Nosodenanwendung in Diagnostik und therapie. Uelzen, Germany, ML-Verlage; 1977.
- Zhu Z. Research advances in the electrical specificity of meridians and acupuncture points. American Journal of Acupuncture. 1981;9:203–216.
- Brown ML, Ulett GA, Stern JA. Acupuncture loci: techniques for location. Am J Chin Med. 1974;2:67–74. doi: 10.1142/S0192415X74000080.
- Reichmanis M, Marino AA, Becker RO. Laplace plane analysis of transient impedance between acupuncture points Li-4 and Li-12. IEEE Trans Biomed Eng. 1977;24:402–405.
- Nakatani Y. An aspect of the study of Ryodoraku. Clinic of Chinese Medicine. 1956;3:54–56.
- Niboyet JEH, Bourdiol RJ, Regard PG. Traité d'acupuncture. Sainte-Ruffine,, Maissonneuve; 1970. Traite d'acupuncture; pp. 140–351.
- Langevin HM, Churchill DL, Fox JR, Badger GJ, Garra BS. Biomechanical response to acupuncture needling in humans. J Appl Physiol. 2001;91:2471–2478.
- Langevin HM, Churchill DL, Cipolla MJ. Mechanical signaling through connective tissue: A mechanism for the therapeutic effect of acupuncture. FASEB J. 2001;15:2275–2282. doi: 10.1096/fj.01-0015hyp.
- Langevin HM, Churchill DL, Wu J, Badger GJ, Yandow JA, Fox JR, Krag MH. Evidence of connective tissue involvement in acupuncture. FASEB J. 2002;16:872–874.
- Langevin HM, Yandow JA. Relationship of acupuncture points and meridians to connective tissue planes. Anat Rec (New Anat) 2002;269:257–265. doi: 10.1002/ar.10185.
- Ho MW, Knight DP. The acupuncture system and the liquid crystalline collagen fibers of the connective tissues. Am J Chin Med. 1998;26:251–263. doi: 10.1142/S0192415X98000294.
- Oschman JL. Energy medicine : the scientific basis. Edinburgh ; New York, Churchill Livingstone; 2000. p. xv, 275 p..
- Deadman P, Al-Khafaji M, Baker K. A Manual of Acupuncture. East Sussex, Journal of Chinese Medicine Publications; 1998.
- Cheng XM. Acupuncture Reference Book. , GuiZhou Publishing; 1995.
- Cheng H, Teng L. Chinese acupuncture and moxibustion. In: Cheng H and Teng L, editor. Chapter 14: Acupuncture Techniques. 1st. Beijing, Foreign Language Press; 1987. pp. 322–329.
- Beijing, Shanghai and Nanjing Colleges of Traditional Chinese Medicine . Essentials of Chinese Acupuncture. Beijing, Foreign Language Press; 1980.
- O'Connor J, Bensky D, Shanghai Zhong yi xue yuan. Acupuncture : a comprehensive text. Chicago, Eastland Press; 1981. p. xvi, 741 p., [3] folded leaves of plates.
- Lukaski HC. Regional bioelectrical impedance analysis: applications in health and medicine. Acta Diabetol. 2003;40 Suppl 1:S196–9. doi: 10.1007/s00592-003-0064-4.
- Salazar Y, Bragos R, Casas O, Cinca J, Rosell J. Transmural versus nontransmural in situ electrical impedance spectrum for healthy, ischemic, and healed myocardium. IEEE Trans Biomed Eng. 2004;51:1421–1427. doi: 10.1109/TBME.2004.828030.
- Cinca J, Warren M, Carreno A, Tresanchez M, Armadans L, Gomez P, Soler-Soler J. Changes in myocardial electrical impedance induced by coronary artery occlusion in pigs with and without preconditioning: correlation with local ST-segment potential and ventricular arrhythmias. Circulation. 1997;96:3079–3086.
- Ellenby MI, Small KW, Wells RM, Hoyt DJ, Lowe JE. On-line detection of reversible myocardial ischemic injury by measurement of myocardial electrical impedance. Ann Thorac Surg. 1987;44:587–597.
- Fallert MA, Mirotznik MS, Downing SW, Savage EB, Foster KR, Josephson ME, Bogen DK. Myocardial electrical impedance mapping of ischemic sheep hearts and healing aneurysms. Circulation. 1993;87:199–207.
- Steendijk P, van der Velde ET, Baan J. Dependence of anisotropic myocardial electrical resistivity on cardiac phase and excitation frequency. Basic Res Cardiol. 1994;89:411–426. doi: 10.1007/BF00788279.
- Tsai JZ, Cao H, Tungjitkusolmun S, Woo EJ, Vorperian VR, Webster JG. Dependence of apparent resistance of four-electrode probes on insertion depth. IEEE Trans Biomed Eng. 2000;47:41–48. doi: 10.1109/10.817618.
- Tsai JZ, Will JA, Hubbard-Van Stelle S, Cao H, Tungjitkusolmun S, Choy YB, Haemmerich D, Vorperian VR, Webster JG. Error analysis of tissue resistivity measurement. IEEE Trans Biomed Eng. 2002;49:484–494. doi: 10.1109/10.995687.
- Tsai JZ, Will JA, Hubbard-Van Stelle S, Cao H, Tungjitkusolmun S, Choy YB, Haemmerich D, Vorperian VR, Webster JG. In-vivo measurement of swine myocardial resistivity. IEEE Trans Biomed Eng. 2002;49:472–483. doi: 10.1109/10.995686.
- Haemmerich D, Staelin ST, Tsai JZ, Tungjitkusolmun S, Mahvi DM, Webster JG. In vivo electrical conductivity of hepatic tumours. Physiol Meas. 2003;24:251–260. doi: 10.1088/0967-3334/24/2/302.
- Yang W, Chang R. Investigation of lower resistance meridian I. Method of investigation. Peking University Academic Journal. pp. 128–136.
- Zhang W, Xu R, Zhu Z. The influence of acupuncture on the impedance measured by four electrodes on meridians. Acupunct Electrother Res. 1999;24:181–188.
- Zhang W, Zhuang F, Tian Y, Li H. [A simulating study of biophysical features along meridians on a gel model] Sheng Wu Yi Xue Gong Cheng Xue Za Zhi. 2001;18:357–361.
Source: PubMed