PC6 is a classic acupuncture point in traditional Chinese medicine. It is considered to be effective when treating cardiovascular disorders. In the present review the authors have focused on the neurophysiological bases of the effects of PC6 stimulation on cardiovascular mechanisms. Experimental studies have shown that the hypothalamic rostral ventrolateral medulla, arcuate nucleus and ventrolateral periaqueductal gray are involved in acupuncture attenuation of sympathoexcitatory cardiovascular reflex responses. This long-loop pathway also appears to contribute to the long-lasting, acupuncture-mediated attenuation of sympathetic premotor outflow and excitatory cardiovascular reflex responses. Acupuncture of PC6 modulates the activity in the cardiovascular system, an effect that may be attributed to attenuation of sympathoexcitatory cardiovascular reflex responses.
Get full access to this article
View all access options for this article.
References
1.
MaKW. Acupuncture: its place in the history of Chinese medicine. Acupunct Med2000;18:88-99.
2.
MiddlekauffHR. Acupuncture in the treatment of heart failure. Cardiol Rev2004;12:171-3.
3.
SchoenAM. Veterinary acupuncture: ancient art to modern medicine. St Louis, Missouri, USA: Mosby, 2001;19–23, 127-48.
4.
TamKC, YiuHH. The effect of acupuncture on essential hypertension. Am J Chin Med (Gard City NY)1975;3:369-75.
5.
RichterA, HerlitzJ, HjalmarsonA.Effect of acupuncture in patients with angina pectoris. Eur Heart J1991;12:175-8.
BallegaardS, JensenG, PedersenF, Acupuncture in severe, stable angina pectoris: a randomized trial. Acta Med Scand1986;220:307-13.
8.
GaoZW, YuXZ, ShenAX, Clinical observations on treatment of 220 cases of arrhythmia with acupuncture. Compilation of the abstract of acupuncture and moxibustion papers (abstract). Beijing: World Federation of Acupuncture-MoxibustionStudies. The First World Conference on Acupuncture-Moxibustion1987;13–14.
9.
LiP, Tjen-A-LooiSC, LonghurstJC. Excitatory projections from arcuate nucleus to ventrolateral periaqueductal gray in electroacupuncture inhibition of cardiovascular reflexes. Am J Physiol Heart Circ Physiol2006;290:H2535–42.
10.
Tjen-A-LooiSC, LiP, LonghurstJC. Midbrain vIPAG inhibits rVLM cardiovascular sympathoexcitatory responses during acupuncture. Am J Physiol Heart Circ Physiol2006;290:2543-53.
11.
Tjen-A-LooiSC, LiP, LonghurstJC. Role of medullary GABA, opioids, and nociceptin in prolonged inhibition of cardiovascular sympathoexcitatory reflexes during electroacupuncture in cats. Am J Physiol Heart Circ Physiol2007;293:3627-35.
12.
TsouMT, HoJY, LinCH, Proteomic analysis finds different myocardial protective mechanisms for median nerve stimulation by electroacupuncture and by local somatothermal stimulation. Int J Mol Med2004;14:553-63.
13.
LiP.Neural mechanisms of the effect of acupuncture on cardiovascular diseases. Satellite Symposium of 34th World Congress of the International Union of Physiological Sciences (IUPS), Electroacupuncture: is there a physiological basis? Auckland, New Zealand, pp 5. International Congress Sciences2002;1238:71-7.
14.
LiP, PitsillidesKF, RendigSV, Reversal of reflex-induced myocardial ischemia by median nerve stimulation: a feline model of electroacupuncture. Circulation1998;97:1186-94.
15.
CrisostomoMM, LiP, Tjen-A-LooiSC, Nociceptin in rVLM mediates electroacupuncture inhibition of cardiovascular reflex excitatory response in rats. J Appl Physiol2005;98:2056-63.
16.
LinJH, ShihCH, KaphleK, Acupuncture effects on cardiac functions measured by cardiac magnetic resonance imaging in a feline model. Evid Based Complement Alternat Med2010;7:169-76.
17.
NapadowV, DhondRP, PurdonP, Correlating acupuncture FMRI in the human brainstem with heart rate variability. Conf Proc IEEE Eng Med Biol Soc2005;5:4496-9.
Tjen-A-LooiSC, LiP, LonghurstJC. Processing cardiovascular information in the vlPAG during electroacupuncture in rats: roles of endocannabinoids and GABA. J Appl Physiol2009;106:1793-9.
20.
FuLW, LonghurstJC. Electroacupuncture modulates vlPAG release of GABA through presynaptic cannabinoid CB1 receptors. J Appl Physiol2009;106:1800-9.
21.
SakataniK, KitagawaT, AoyamaN, Effects of acupuncture on autonomic nervous function and prefrontal cortex activity. Adv Exp Med Biol2010;662:455-60.
22.
ChangS, ChaoWL, ChiangMJ, Effects of acupuncture a. Neiguan (PC6) of the pericardial meridian on blood pressure and heart rate variability. Chin J Physiol2008;51:167-77.
23.
LiJS, YanJ, HeJF, (Effects of electroacupuncture on c-fos expression in nucleus of the solitary tract and electrocardiogram ST(II) in myocardial ischemia rats). Zhen Ci Yan Jiu2009;34:171-4.
24.
ChaoDM, ShenLL, Tjen-A-LooiS, Naloxone reverses inhibitory effect of electroacupuncture on sympathetic cardiovascular reflex responses. Am J Physiol1999;276:H2127–34.
25.
Tjen-A-LooiSC, LiP, LonghurstJC. Prolonged inhibition of rostral ventral lateral medullary premotor sympathetic neurons by electroacupuncture in cats. Auton Neurosci2003;106:119-31.
26.
ZhouW, FuLW, GuoZL, Role of glutamate in rostral ventrolateral medulla in acupuncture-related modulation of visceral reflex sympathoexcitation. Am J Physiol Heart Circ Physiol2007;292:1868-75.
27.
LiP, Tjen-A-LooiSC, GuoZL, An arcuate-ventrolateral periaqueductal gray reciprocal circuit participates in electroacupuncture cardiovascular inhibition. Auton Neurosci2010;158:13-23.
28.
HoladayJW. Cardiovascular effects of endogenous opiate systems. Am J Physiol1983;276:2127-34.
29.
JinYZ, CaoQS, ZhuangD.Function of nucleus of solitary tract in the correlation between heart and acupoint neiguan. J Tradit Chin Med1988;8:61-8.
30.
LiP, Tjen-A-LooiS, LonghurstJC. Rostral ventrolateral medullary opioid receptor subtypes in the inhibitory effect of electroacupuncture on reflex autonomic response in cats. Auton Neurosci2001;89:38-17.
31.
MoazzamiA, Tjen-A-LooiSC, GuoZL, Serotonergic projection from nucleus raphe pallidus to rostral ventrolateral medulla modulates cardiovascular reflex responses during acupuncture. J Appl Physiol2010;108:1336-46.
32.
GuoZL, MoazzamiAR, Tjen-A-LooiS, Responses of opioid and serotonin containing medullary raphe neurons to electroacupuncture. Brain Res2008;1229:125-36.
33.
ColemanMJ, DampneyRA. Powerful depressor and sympathoinhibitory effects evoked from neurons in the caudal raphe pallidus and obscurus. Am J Physiol1995;268:R1295–302.
34.
BagoM, MarsonL, DeanC.Serotonergic projections to the rostroventrolateral medulla from midbrain and raphe nuclei. Brain Res2002;945:249-58.
35.
OrerHS, GebberGL, BarmanSM. Role of serotonergic input to the ventrolateral medulla in expression of the 10-Hz sympathetic nerve rhythm. Am J Physiol Regul Integr Comp Physiol2008;294:R1435–44.
36.
TakayamaS, SekiT, WatanabeM, Brief effect of acupuncture on the peripheral arterial system of the upper limb and systemic hemodynamics in humans. J Altern Complement Med2010;16:707-13.
37.
HuntSPLovickTA. The distribution of serotonin, met-enkephalin and beta-lipotropin-like immunoreactivity in neuronal perikarya of the cat brainstem. Neurosci Lett1982;30:139-45.
38.
ArvidssonU, CullheimS, UlfhakeB, Distribution of enkephalin and its relation to serotonin in cat and monkey spinal cord and brain stem. Synapse1992;11:85-104.
39.
KrukoffTL. Central actions of nitric oxide in regulation of autonomic functions. Brain Res Brain Res Rev1999;30:52-65.
40.
Tjen-A-LooiSC, PhanNT, LonghurstJC. Nitric oxide modulates sympathoexcitatory cardiac-cardiovascular reflexes elicited by bradykinin. Am J Physiol Heart Circ Physiol2001;281:2010-17.
41.
WangJ, ChenZJ, LuoCQ, (The expression of neuronal nitric oxide synthase in caudal medulla of two-kidney one clip Goldblatt hypertension rat). Sheng Li Xue Bao2002;54:175-8.
42.
GuoZL, LonghurstJC. Activation of nitric oxide-producing neurons in the brain stem during cardiac sympathoexcitatory reflexes in the cat. Neuroscience2003;116:167-78.
43.
WangC, TianYF, ZhouD, (Influence of electroacupuncture on myocardial NO and NOS and intracellular Ca2+ contents in myocardial ischemia-reperfusion injury rats). Zhen Ci Yan Jiu2010;35:113-17.
44.
ZhongH, LiGZ. (Study on the mechanism of electroacupuncture of ‘Neiguan’ (PC 6) in inhibiting ventricular arrhythmia induced by hypothalamic electrostimulation in the rabbit). Zhen Ci Yan Jiu2009;34:43-7.
45.
World Health Organization. Guidelines for Clinical Research in Acupuncture. Western Pacific series no. 15. Manila, Philippines: WHO Regional Office for the Western Pacific, 1995.
46.
JoHG, JoGH. Electroencephalogram activity induced by magnetic stimulation on heart meridian. Neurosci Lett2011;495:107-9.
47.
ZhouYiSyuuW, HsiaoI, LinVW, Modulation of cardiovascular excitatory responses in rats by transcutaneous magnetic stimulation: role of the spinal cord. J Appl Physiol2006;100:926-32.
