大鼠中脑导水管周围灰质内微量注射强啡肽抗体对不同频率电针镇痛的影响

<正> 强啡肽(Dynorphin)是1979年Goldstain等发现的一种内源性阿片肽,它在离体豚鼠回肠标本上具有强烈的阿片样活性。近年来,对于它在体内不同中枢部位的痛觉调制作用以及在电针镇痛中所起的作用日益引起人们的兴趣。在脊髓内,已有资     

针刺镇痛频率特异性的进一步证明

我们以往的工作证明 ,不同频率的电针会引起中枢不同种类的神经肽释放 ,产生不同的生理作用和治疗效果 ,近年来又有一些新的资料进一步证明并扩展了这一假说。1 .2Ｈｚ电针引起中枢内吗啡肽 (ＥＭ)释放 ,1 0 0Ｈｚ无效ＥＭ是近年新发现的一种阿片肽 ,还不清楚何种频率的电针可促进其释放。①将ＥＭ抗体注入大鼠脊髓蛛网膜下腔可阻断 2Ｈｚ电针镇痛 ,而不影响 1 0 0Ｈｚ电针镇痛 (Ｈａｎ ,ｅｔａｌ.ＮｅｕｒｏｓｃＬｅｔｔ,1 999,2 74:75) ;②将ＥＭ抗体或μ受体拮抗剂ＣＴＯＰ注入小鼠脑室 ,阻断 2Ｈｚ电针镇痛而不影响 1 0 0Ｈｚ电针镇痛 (…     

导水管周围灰质(PAG)对中缝大核(NRM)神经元活动的影响及其在电针足三里镇痛中的作用

<正> 我国多年来关于针刺镇痛原理的研究表明,针刺镇痛作用是通过神经系统实现的。近年来证明脑内存在有内在的痛控制系统。它可通过延脑中缝大核下行抑制脊髓背角神经元,阻止痛信息的传入而起到镇痛作用。我们和一些研究者报道了刺激NRM可加强针刺的镇痛作用,而毁损NRM可使针刺的镇痛作用减弱。近来我们直接记录NRM神经元放电看到电针可激活NRM神经元的自发放电并抑制其伤害性反应,而且纳洛酮可以翻转此种效应     

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     

镨、铽、EGTA、吗啡和电针镇痛作用比较

<正> 以辐射热-甩尾法测痛,电针小鼠“人中”、“承浆”穴,观察二价阳离子与镧系元素的相互关系,并着重比较镧系元素铽,错、EGTA、吗啡和电针镇痛的特性。实验结果表明,腹腔预先注射纳洛酮使脑室内注射Tb~(+++)、Pr~(+++)、吗啡或电针镇痛效果全部或部分对抗,此时伴有脑Ca~(++)水平增设;动物出现痛觉过敏。但纳洛酮处理不影响EGTA的镇痛作用和脑Ca~(++)水平。蛋白质合成抑制剂环己亚胺能降低Tb~(+++)和Pr~(+++)的镇痛作用,增高     

Acupuncture analgesia: a review of its mechanisms of actions

The mechanism of acupuncture analgesia (AA) has been widely explored since the 1970s. Early studies investigated the relationship between acupuncture and endogenous opiates (beta-endorphin, enkephalin, endomorphin and dynorphin). Before the 1990s, most experts agreed on the concept that in normal animal models, lower frequency electroacupuncture (EA) stimulates the release of beta-endorphin, enkephalin and endomorphin, which in turn activates the mu- and delta-opioid receptors, and that higher frequency EA stimulates dynorphin which activates the kappa-opioid receptor. Besides endogenous opiates, our studies have focused on serotonin. The serotoninergic descending inhibitory pathway is suggested to be an important mechanism of acupuncture analgesic, collaborating with endogenous opiates. Many efforts have been made to clarify these mechanisms, but to date no satisfactory consensus has been reached. In the late 1990s, researchers began to focus on the different analgesic effects of EA between normal and hyperalgesic animal models. Published data from these studies imply that normal and hyperalgesic animals respond differently to EA. Results from experiments on the anti-hyperalgesia effect of EA have raised a new issue about the influences of EA on receptors to excitatory amino acid in the spinal cord level. Results from various studies have shown that these receptors play a role in the mechanism of AA. Recently, research on the autonomic nervous system (ANS) seem to indicate its connection with acupuncture. The inflammatory reflex (via the ANS) might be a crucial part of anti-hyperalgesia elicited by acupuncture, and this reflex, which regulates the immune system in the organism, can elucidate not only the mechanism of AA but also the mechanism of acupuncture applied to other inflammatory conditions. Innovation of functional image study enables us to analyze the responses of cortex on living human body to acupuncture. However, results of these experiments are still controversial. After 30 years of acupuncture research, there are still many puzzles left to be solved regarding the mechanism of AA.     

中脑导水管周围灰质内催产素在电针镇痛中的作用及机制的实验研究

我们以往的工作表明 ,侧脑室和脊髓蛛网膜下腔内注射催产素 (ＯＴ)能明显提高大鼠电针镇痛效应 ,注射抗催产素血清 (ＡＯＴＳ)则能显著降低电针镇痛效应。提示 ,中枢神经系统内的催产素在电针镇痛的复杂过程中发挥着一定作用。中脑导水管周围灰质 (ＰＡＧ)是电针镇痛的关键部位 ,其内含有丰富的ＯＴ、ＯＴ神经末梢及ＯＴ受体 ,但中枢ＯＴ在电针镇痛中的作用是否与之有关 ,作用机制怎样 ?是一个引人关注的问题。本工作以钾离子透入法 ,以甩尾法作为疼痛指标 ,测定大鼠痛阈 ,观察ＰＡＧ注射ＯＴ、ＡＯＴＳ、纳洛酮 (Ｎｘ)、抗 β 内啡肽血清 (…     

Retrosplenial cortex is involved in analgesia induced by 2- but not 100-Hz electroacupuncture in the rat tail-flick test

This study examined whether or not the antinociceptive effect of 2- or 100-Hz electroacupuncture (EA) depends on the integrity of the retrosplenial cortex (RSC). Rats were taken for determination of tail-flick latency before and after injection of saline or 2% lidocaine (0.25 μl) into the retrosplenial cortex (RSC) bilaterally. Five minutes later, they were submitted to a 20-minute period of 2 Hz, 100 Hz, or sham EA at the Zusanli and Sanyinjiao acupoints bilaterally, and tail-flick latency was measured within 30 seconds after the end of stimulation and at 5-minute intervals for up to 30 minutes. EA at a frequency of either 2 or 100 Hz induced a strong and long-lasting inhibition of the tail-flick reflex in rats treated with saline (0.25 μl) injected into the RSC. The analgesia produced by 2-Hz EA lasted for a shorter time in lidocaine-treated rats. By contrast, RSC impairment did not change the analgesic effect of 100 Hz EA. The integrity of the RSC is implicated in the duration of analgesia induced by low-frequency EA but is not essential for the analgesic effects evoked by high-frequency EA.     

家兔中脑导水管周围灰质和脊髓内的P物质在电针镇痛中有相反的作用

<正> 1931年Von Euler和Gaddum从马脑和小肠中提取出P物质(SP),半个世纪以来,对其生理药理作用进行了大量研究,证明P物质是一种重要的肽类神经递质,特别是在痛觉调制中起重要作用。在脊髓背角和三叉神经核中,P物质可能是初级神经元传递“疼痛信息”的物质,但在中枢神经系统(CNS)不同部位作用的特异性及其在针刺镇痛中的意义,尚未见系统报     

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.