电针频率是决定家兔电针镇痛效果是否能被纳洛酮阻断的重要因素

<正> 人们在临床实践中体验到,在同一穴位上运用不同的针刺手法可产生不同的治疗效果。这一现象愈来愈引起针灸原理研究工作者的兴趣。近二十年来针刺镇痛原理的研究日益深入,业已证明,电针刺激可使中枢神经系统释放阿片肽产生镇痛作用。但阿片颉颃剂纳洛酮阻断大鼠电针镇痛的程度和所需的剂量与电针频率密切相     

激活GABA_B受体在针刺镇痛中的作用

目的 :脑室注射γ 氨基丁酸 (GABA)A受体的拮抗剂荷包牡丹碱 (Bic)未能阻断针刺镇痛效应 ,微电泳导入Bic部分阻断电针抑制脊髓背角伤害性反应 ,说明GABA可通过激活A受体参与针刺镇痛中脊髓节段性抑制。本文进一步探讨了激活GABAB 受体在针刺镇痛中的作用。方法 :以辐射热照射大鼠尾部引起甩尾反射潜伏期作为痛阈的指标 ,以针刺“次”穴后痛阈最大变化百分率判断镇痛效应 ,观察脑室注射 (icv) 5μL或蛛网膜下腔 (ith)注射 1 0 μLGABAB 受体的拮抗剂CGP 55845对针刺镇痛效应的影响。每组 6～ 8例。结果 :icvGABA( 1 2 5μg、2 50 μg、50 0 μg)或GABAB 受体激动剂苯氯丁氨酸 (Baclofen ,2 5ng、2 50ng、2 50 0ng)可产生剂量依赖的镇痛效应。icvCGP 55845( 5ng、50ng)可大部分阻断GABA和Baclofen的镇痛效应。针刺双侧“次”穴( 50Hz,1～ 2mA) 1 0min ,痛阈提高到针前值的 ( 1 42 .5± 2 .1 ) % ,镇痛效应显著。针前icvCGP55845针后痛阈分别提高到 ( 1 1 1 .2± 1 .2 ) %和 ( 1 1 2 .1± 1 .1 ) % ,阻断率分别为 73 .7%和 71 .6% ,和事先icv生理盐水 ( 1 43 .7± 2 .0 ) %相比 ,阻断效应明显。若针刺前ithCGP 55845( 50ng、50 0ng) ,也能明显阻断针刺镇痛效应。结论 :脑内注射GABA或Baclofen可通过激?     

慢性疼痛及其诱发负面情绪的神经环路及电针调节机制（英文）

Chronic pain is a common clinical condition that is frequently linked to negative emotions such as anxiety and depression.Electroacupuncture(EA) has been shown to have beneficial therapeutic effects in analgesia and the reduction of pain-induced negative emotions,and promising results have been obtained in the study of its neural circuit mechanism.Optogenetics,chemogenetics,neurocircuit tracing,functional magnetic resonance imaging(fMRI),and conditional gene knockdown experiments have shown that...     

咪唑啉受体参与痛觉调制和针刺镇痛

目的 :观察咪唑啉受体在痛觉调制和针刺镇痛中的作用。方法 :本文以辐射热照射致甩尾反射潜伏期作为测痛的指标 ,采用蛛网膜下腔注射 (ith)咪唑啉受体的激动剂和拮抗剂的方法观察咪唑啉受体对痛阈和针刺镇痛效应的影响。结果 :ith可乐宁和电针双侧“次”穴可产生明显的镇痛效应 ,均可被事先注射咪唑啉受体的拮抗剂苯恶唑 (Idazoxan)所阻断。结论 :说明激活咪唑啉受体可能是可乐宁和电针镇痛效应的共同脊髓机制 ,但是没有观察到可乐宁明显加强针刺镇痛的协同作用     

电针对大鼠皮层SmI区神经元自发放电的影响

为了探讨针刺镇痛中皮层ＳｍＩ区对Ｐｆ神经元的下行调节是否与针刺激活ＳｍＩ区神经元有关,本文观察了电针对大鼠皮层 ＳｍＩ区神经元自发放电的影响。结果发现,电针可引起大鼠皮层ＳｍＩ区神经元的自发放电明显增加（Ｐ＜０．０５）。由此表明,在针刺镇痛中皮层ＳｍＩ区对丘脑Ｐｆ神经元伤害性反应的抑制作用是通过针刺激活皮层神经元而实现的。     

中脑腹侧被盖区参与低频或高频电针对甩尾实验的镇痛效应

中脑腹侧被盖区 (ｖｅｎｔｒａｌｔｅｇｍｅｎｔａｌａｒｅａ,ＶＴＡ)的ＤＡ能通路在成瘾药物中的奖赏作用已被广泛研究。近年来有报道此通路参与吗啡的镇痛作用。而电针镇痛的机制与吗啡镇痛有相似之处 ,但在电针的镇痛效应中是否有此通路的参与尚无研究。本研究利用电针及核团损毁技术研究了中脑ＶＴＡ的ＤＡ能通路是否参与不同频率 (2Ｈｚ,1 0 0Ｈｚ)电针对甩尾实验的镇痛效应。不同频率电针的ＳＤ大鼠分别随机分为两组 :假损毁组及损毁组。随后通过脑立体定位技术分别进行大鼠双侧ＶＴＡ的假损毁 (注入溶 6 ＯＨＤＡ的溶剂——— 0 .3%…     

针刺“后三里”穴不同留针时间对小鼠甩尾痛阈的影响

目的:通过观察针刺"后三里"穴对小鼠热水甩尾痛阈的影响,探讨留针时间与针灸效应的关系.方法:健康小鼠24只,随机分为针刺即刻组(A组)、留针10 min组(B组)、留针20 min组(C组)、留针30 min组(D组),每组6只.手针针刺小鼠"后三里"穴后,以50℃热水浸鼠尾,分别记录针刺即刻、留针10 min、留针20 min、留针30 mind、鼠甩尾潜伏期,对比鼠尾入水至甩尾出水的时间间隔.结果:A、C两组针刺"后三里"能显著提高小鼠的甩尾痛阈(均P<0.01),而B、D两组针刺"后三里"对小鼠的甩尾痛阈提高不显著(均P>0.05).留针30 min内针刺镇痛效应呈波浪形曲线,留针20 min小鼠甩尾潜伏期达到最大值,即针刺达到最大镇痛效果.结论:手针镇痛的留针时间以20 min为最佳.     

持续电针引起耐受及其与吗啡镇痛的交叉耐受

<正> 我们曾经报告,给大鼠反复、间断电针可以使针效逐渐下降以至消失,即产生电针耐受。本工作进一步证明,应用持续长时间电针,也可引起大鼠电针耐受.并观察了持续电针所致耐受发生、发展和恢复的规律及其与吗啡的交叉耐受现象.方法【测痛和电针】实验用160～220克雌性大鼠,固定于特制固定器内,以辐射热-甩尾法进行测痛,实验开始时连续测痛三次,每次间隔5分钟,取三次测痛的均值为基础痛阈。电针穴位取双侧“足三里”和“三阴交”,以国产57-6型电针仪给予疏密式脉     

Quantification of electroacupuncture-induced neural activity by analysis of functional neural imaging with monocrystalline iron oxide nanocolloid enhancement

The purpose of this study was to investigate the neural activity of electroacupuncture (EA) quantitatively. The responses of Sprague-Dawley rats' brain to EA on acupoints--Hegu (LI 4) and Neiguan (PC 6)--were detected by monocrystalline iron oxide nanoparticle (MION)-enhanced functional magnetic resonance imaging (MION-fMRI), which is a 1.5 T horizontal spectrometer equipped with a circular polarized extremity coil. During EA at LI 4, neural activities were analyzed by analysis of functional neural images (AFNI). Neural activation was detected at the structures of hypothalamus, thalamus, hippocampus, and the cortex, while neural deactivation existed at the areas adjacent to the activated sites. EA on PC 6 activated the structures of thalamus and the cortex but deactivated the structures of hypothalamus and hippocampus. The brain responses to EA existed in different areas of activation and deactivation despite stimulating the same acupoint. Additionally, distinct brain neuroimages were produced through stimulating different acupoints. This study suggests that fMRI with AFNI is a good approach to quantifying brain activities. This innovative method brings new perspective into the mechanisms of acupuncture.     

The role of substance P in electroacupuncture analgesia and its relation to enkephalins in the rat brain]

In order to understand the role of substance P (SP) in the brain and the relationship between SP and enkephalins in the electroacupuncture analgesia (EA), we have observed the influence of SP-antagonist, (D-Arg', D-Phe5, D-Trp7.9, Leu11) -SP (DADPDTL) injected intracerebroventricularly (icv) on EA and the change of the level of SP in the brain regions of the rat during EA. We have made a further observations on the influences of the naloxone (NX) on the che change of the content of SP induced by EA and DADPDTL on the increase in Leu-enkephalins (LEK) induced by EA. The Wistar rats were used in the experiment. The latency of the tail flick, immersing the tip of rat tail (4 cm) into hot-water of 50 degrees C, was taken as the pain threshold. The drugs were injected icv via plastic cannulae implanted in the bilateral ventricles. The EA was applied to the point of "Zusanli" (S36). The contents of SP and LEK were determined radioimmunoassay in the hypothalamus, mid-brain, striatum and pons-medulla-oblongata. The pain threshold was increased by 48 +/- 9% (P less than 0.01) after EA. But icv injection of DADPDTL decreased the pain threshold by 14 +/- 7% after EA. The result suggests that DADPDTL can antagonize the effect of EA and that SP in the brain is involved in EA. After EA the contents of SP in the hypothalamus and mid-brain of the rats were decreased by 29% and 28% in comparison with that of the control group respectively (both of them, P less than 0.05), but the contents of SP in the striatum and pons-medulla-oblongata had no significant change.(ABSTRACT TRUNCATED AT 250 WORDS)     

Antinociception of heterotopic electro-acupuncture mediated by the dorsolateral funiculus

We investigated the inhibitory pathways that mediate the antinociceptive effects of heterotopic electro-acupuncture (EA) on formalin injection-induced pain in rats. EA (2 ms, 10 Hz, 3 mA) was delivered to heterotopic acupoints HT(7) and PC(7) for 30 min; this was followed immediately by subcutaneous injection of formalin into the left hind paw of rats. Naltrexone (10 mg/kg, i.p.), an opioid receptor antagonist, was administered to evaluate the involvement of endogenous opioids. The dorsolateral funiculus (DLF), which is a descending pathway that inhibits pain, was transected at the ipsilateral T10-11 level of the thoracic spinal cord. EA inhibited behavioral responses to formalin injection-induced pain and prevented the pain-induced increase in cFos expression in the lumbar spinal cord. Pretreatment with naltrexone did not inhibit the antinociceptive effects of EA on formalin injection-induced pain. Transection of the DLF ipsilateral to the acupuncture site eliminated the antinociceptive effects of EA. These results suggest that the antinociceptive effects of heterotopic EA are mediated by the DLF and not by endogenous opioids.     

The role of negative feedback modulating pain of nucleus raphe magnus in electroacupuncture analgesia

In recent years I am interested in the role of nucleus raphe magnus (NRM) in acupuncture analgesia, NRM is the one of important descending inhibitory systems included in the intrinsic analgesic systems in brain, and we gave more systematic study on the question. The primary results are as follows: 1. Experiments were performed on male rats, unit discharges of NRM were recorded extracellularly with glass electrode. The neurons respond to noxious stimulation were chosen to observe analgesia of EA. The spontaneous firing rates of NRM neurons were about 0.5-20 Hz, a few of them over 20Hz or have no any discharges. NRM neurons have not often responses to nonnoxious stimulation (to brush hair) or only have a light responses and adaptation appeared fast. But responses of them to noxious stimulation (to clamp or to prick skin) or electro-stimulation (over 6V) were obviously displayed with excitatory (increasing firing rates) or inhibitory (decreasing) types. The spontaneous firing rates of excitatory NRM neurons were lower than that of inhibitory neurons. In addition, a few excitatory-inhibitory reversible type NRM neurons were found unexpected, and the reversal of response were related to background firing rates. During low firing rates, the response was an excitatory one, and during high firing rates, it became an inhibitory one. 2. EA of 'Zusanli' could activate NRM neurons, increasing spontaneous firing rates, and inhibit their nociceptive responses. The effect induced by EA could be reversed by naloxone (I.P.). 3. Raphe-spinal neurons in NRM were identified by antidromic activation and collision technology, their axons project to dorsal horn of spinal cord via dorsal lateral fasciculus (DLF), that seem to be centrifugal units.(ABSTRACT TRUNCATED AT 250 WORDS)     

The physiological mechanisms of 2 Hz electroacupuncture: a study using blink and H reflex

Our previous studies have shown that the cerebral cortex modulates the physiological mechanisms of acupuncture. However, the role of the brain stem and spinal cord in acupuncture remains unclear. The present study investigated the action of the brain stem and spinal cord in acupuncture. A total of eight healthy adult volunteers were studied. Electrical stimulation of the supraorbital nerve in the supraorbital foramen was used to evoke the blink reflex. Electrical stimulation of the posterior tibial nerve in the right popliteal fossa was used to evoke the H reflex. Electroacupuncture (EA) of 2 Hz was applied to the Zusanli acupoint in the right or left leg. The area of the R1 and R2 components of the blink reflex, and the greatest H/M ratio and H-M interval of the H reflex were measured before EA, during EA and at various post-EA periods. These data were analyzed quantitatively by a computerized electromyographic examination system. The results indicate that EA did not change the R1 and ipsilateral R2 components of the blink reflex. EA depressed the contralateral R2 component of the blink reflex 10 minutes and 40 minutes after the start of EA, but not after 5 minutes. EA applied to the Zusanli acupoint did not change the H/M ratio or the H-M interval of the H reflex. The results of this study indicate that 2 Hz EA of the Zusanli acupoint does not change the R1 component of the blink reflex, and the H/M ratio and the H-M interval of the H reflex, suggesting that 2 Hz EA does not change the monosynaptic reflex in the brain stem and spinal cord in humans. We also found that EA at 2 Hz depressed the contralateral but not the ipsilateral R2 component of the blink reflex, suggesting that longer pathways, perhaps including the cerebral cortex, may play a role in the physiological mechanisms responsible for the effectiveness of acupuncture.     

不同频率电针对大鼠尾壳核头部一氧化氮合酶表达的影响

低频 (2Hz)和高频 (1 2 8Hz)电针大鼠“合谷”穴 ,采用还原型尼克酰胺嘌呤二核苷酸脱氢酶 (NADPH d)法 ,显示不同频率电针对尾壳核头部各区一氧化氮合酶 (NOS)表达的影响。结果表明 ,低频和高频电针均可使尾壳核头部NOS表达增强 ,高频电针上调尾壳核头部NOS表达更为显著     

双侧损毁腹外侧眶皮层对电针抑制大鼠甩尾反射的影响

本研究在浅麻大鼠发现,电解损毁双侧腹外侧眶皮层（VLO）明显减弱强电针“足三里”穴对大鼠甩尾（TF）反射的抑制效应;但对弱电针的抑制效应无明显影响。表明VLO参与伤害感受调制,它可能在强电针兴奋细纤维（Ⅲ、Ⅳ类）产生的镇痛中具有重要作用。本研究为我们提出的脊髓-丘脑中央下核（Sm）-VLO-导水管周围灰质（PAG）-脊髓负反馈痛调制环路的设想提供了支持。     

ACUPUNCTURE EFFECT ON GENE EXPRESSION OF c-fosmRNA, ppENKmRNA, iNOSmRNA AND iNOS ACTIVITY IN THE MOUSE SPINAL CORD

Ｉｔｗａｓｒｅｐｏｒｔｅｄｔｈａｔｔｈｅｍｅｔｈｉｏｎｉｎｅｅｎｋｅｐｈａｌｉｎｉｍｍｕｎｏｒｅａｃｔｉｖｉｔｙ(ＭＥＫＩＲ)ａｎｄｌｅｕｃｉｎｅｅｎｋｅｐｈａｌｉｎｉｍｍｕｎｏｒｅａｃｔｉｖｉｔｙ(ＬＥＫＩＲ)ｗｅｒｅａｔｔｅｎｕａｔｅｄｉｎｔｈｅｇｕｉｎｅａｐｉｇ’ｓｓｐｉｎａｌｃｏｒｄａｆｔｅｒａｃｕｐｕｎｃｔｕｒｅｉｎｏｕｒｐｒｅｖｉｏｕｓｅｘｐｅｒｉｍｅｎｔ,ｓｕｇｇｅｓｔｉｎｇｔｈａｔａｃｕｐｕｎｃｔｕｒｅｍａｙｉｎｄｕｃｅｔｈｅｒｅｌｅａｓｅｏｆＭＥＫａｎｄＬＥＫｆｒｏｍｔｈｅｓｐｉｎ…     

家兔中脑导水管周围灰质内注射抗β-内啡肽抗体削弱电针镇痛效果

<正> 本世纪七十年代初,Simon,Pert和 Terenius 三个实验室分别独立地确定在体内特别是中枢神经系统内存在着特异的阿片受体。随后,Hughes 等成功地从猪脑中分离提取出两种具有阿片活性的五肽—甲硫-脑啡肽和亮-脑啡肽。在此以后,人们又从垂体中发现了阿片活性更强的β-内啡肽和强啡肽。这些内源性阿片样物质(OLS)的发现,为疼痛生理之研究打开了新的突破口.1975年,Mayer 等首次报告了静脉内注射特异的阿片受体阻断剂纳络酮可以翻转针刺的镇痛作用.这就提示在针刺镇痛的机制中可能有 OLS 参与,但尚不能明确在OLS 这一族化合物中哪一个具体组分在发挥作用.     

C纤维不是电针镇痛的主要传入纤维,而是弥散性伤害性抑制控制的主要纤维

<正> 电针刺激通过何种纤维传入中枢产生镇痛作用,至今仍有争论。范少光等采用我室常用电针参数,以大鼠行为反应为指标,观察到电针(Electroacupuncture,EA)镇痛信息主要不是由 C 纤维传入。本工作用辣椒素选择性阻断 C 纤维传导后,观察了 EA 和伤害性热刺激(Noxious heat,NH)对脊髓广动力范围(Wide DynamicRange,WDR)神经元抑制作用的影响,进一步对上述问题作探讨。     

毁损大鼠SmI对丘脑Pf神经元针刺镇痛效应的影响及微电泳导入ACh的效应

用多管微电极细胞外记录及微电泳技术,观察到：毁损大鼠皮层SmI后,电针穴位对丘脑束旁核（Pf）神经无伤害性反应的抑制作用被减弱;微电泳导入ACh能抑制SmI毁损大鼠Pf神经元的伤害性反应,其作用与SmI完整时电针对其伤害性反应的抑制效应相似。结果表明,ACh是参与皮层对丘脑Pf神经元针刺镇痛下行调节的神经递质之一。