Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was app...Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was applied in a rat model, adenosine 5-triphosphate disodium in the extracellular space was broken down into adenosine, which in turn inhibited pain transmission by means of an adenosine A1 receptor-dependent process. Direct injection of an adenosine A1 receptor agonist enhanced the analgesic effect of acupuncture. The analgesic effect of acupuncture appears to be mediated by activation of A1 receptors located on ascending nerves. In neuropathic pain, there is upregulation of P2X purinoceptor 3 (P2X3) receptor expression in dorsal root ganglion neurons. Conversely, the onset of mechanical hyperalgesia was diminished and established hyperalgesia was significantly reversed when P2X3 receptor expression was downregulated. The pathways upon which electroacupuncture appear to act are interwoven with pain pathways, and electroacupuncture stimuli converge with impulses originating from painful areas. Electroacupuncture may act via purinergic A1 and P2X3 receptors simultaneously to induce an analgesic effect on neuropathic pain.展开更多
BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism o...BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE: To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING: In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS: Thapsigargin, caffeine, suramin, and adenosine 5'-triphosphate were purchased from Sigma, USA. METHODS: Using Fura-2-based microfluorimetry, intracellular calcium concentration ([Ca^2+]i) was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES: Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2+]i changes. RESULTS: In normal extracellular solution and Ca^2+-free solution, application of thapsigargin (1 μmol/L), a sarcoplasmic reticulum Ca^2+ pump adenosine 5'-triphosphate inhibitor, as well as caffeine (20 mmol/L), a ryanodine receptor agonist, triggered [Ca^2+]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5'-triphosphate (100 μmol/L). In Ca^2+-free conditions, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin (P 〈 0.01), but not by caffeine (P 〉 0.05). In normal, extracellular solution, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin (P 〈 0.05). CONCLUSION: Inositol-1,4, 5-triphosphate (IP3)- and ryanodine-sensitive Ca^2+ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinoreceptor-mediated [Ca^2+]i rise observed in nociceptive trigeminal ganglion neurons. One pathway involves the metabotropic P2Y receptors, which are associated with the IP3 sensitive Ca^2+store, and the second pathway is coupled to ionotropic P2X receptors that induce the Ca^2+ influx.展开更多
Adenosine 5'-triphosphate(ATP) not only participates in various physiological activities as the universal energy currency but also implicates in various pathological processes in living cells. Consequently,sensitiv...Adenosine 5'-triphosphate(ATP) not only participates in various physiological activities as the universal energy currency but also implicates in various pathological processes in living cells. Consequently,sensitive and selective detection ATP in live cells, tissues, as well as environmental samples, are urgently demanded. Due to the simple and convenient operation, economy cost, high selectivity for analyte, well biocompatibility and low cytotoxicity, fluorescent sensors for monitoring ATP have aroused great attention of researchers. In recent years, a large number of fluorescent sensors for detecting ATP have developed. This manuscript summarized most of these sensors and the interaction-mechanism between ATP and sensors, mainly including electrostatic interaction, p-p interaction, covalent bonding or hydrogen bond, or combinations of them, and the advantages of each strategy were also generalized.Here, a viewpoint of classification was shown where the sensors were divided into five typed ones according to the structure of probes used.展开更多
文摘Applying a stimulating current to acupoints through acupuncture needles–known as electroacupuncture–has the potential to produce analgesic effects in human subjects and experimental animals. When acupuncture was applied in a rat model, adenosine 5-triphosphate disodium in the extracellular space was broken down into adenosine, which in turn inhibited pain transmission by means of an adenosine A1 receptor-dependent process. Direct injection of an adenosine A1 receptor agonist enhanced the analgesic effect of acupuncture. The analgesic effect of acupuncture appears to be mediated by activation of A1 receptors located on ascending nerves. In neuropathic pain, there is upregulation of P2X purinoceptor 3 (P2X3) receptor expression in dorsal root ganglion neurons. Conversely, the onset of mechanical hyperalgesia was diminished and established hyperalgesia was significantly reversed when P2X3 receptor expression was downregulated. The pathways upon which electroacupuncture appear to act are interwoven with pain pathways, and electroacupuncture stimuli converge with impulses originating from painful areas. Electroacupuncture may act via purinergic A1 and P2X3 receptors simultaneously to induce an analgesic effect on neuropathic pain.
基金the National Natural Science Foundation of China, No.30670694 the Natural Science Foundation of Anhui Province Department of Education in China, No.2006KJ361B+2 种基金 the National Science Fund for Distinguished Young Scholars of Anhui Medical University, No.GJJQ-0801 the Scientific Research Foundation for Doctor of Anhui Medical University, No. XJ2005006the Special Foundation for Young Scientists in Higher Education Institutions of Anhui Province, No.2010SQRL078
文摘BACKGROUND: Most of the currently available information on purinergic receptors (P2Rs) involved in pain transmission is based on results obtained in dorsal root ganglion or the spinal cord. However, the mechanism of P2Rs in trigeminal neuralgia remains unclear. OBJECTIVE: To investigate changes in the P2R-mediated calcium signaling pathway in nociceptive trigemJnal ganglion neurons. DESIGN, TIME AND SETTING: In vitro experiments were conducted at the Patch-Clamp Laboratory of Comprehensive Experiment Center of Anhui Medical University, China from September 2008 to June 2009. MATERIALS: Thapsigargin, caffeine, suramin, and adenosine 5'-triphosphate were purchased from Sigma, USA. METHODS: Using Fura-2-based microfluorimetry, intracellular calcium concentration ([Ca^2+]i) was measured in freshly isolated adult rat small trigeminal ganglion neurons before and after drug application. MAIN OUTCOME MEASURES: Fluorescent intensities were expressed as the ratio F340/F380 to observe [Ca^2+]i changes. RESULTS: In normal extracellular solution and Ca^2+-free solution, application of thapsigargin (1 μmol/L), a sarcoplasmic reticulum Ca^2+ pump adenosine 5'-triphosphate inhibitor, as well as caffeine (20 mmol/L), a ryanodine receptor agonist, triggered [Ca^2+]i increase in small trigeminal ganglion neurons. A similar response was induced by application of adenosine 5'-triphosphate (100 μmol/L). In Ca^2+-free conditions, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were inhibited in cells pre-treated with thapsigargin (P 〈 0.01), but not by caffeine (P 〉 0.05). In normal, extracellular solution, adenosine 5'-triphosphate-induced [Ca^2+]i transients in small trigeminal ganglion neurons were partly inhibited in cells pre-treated with thapsigargin (P 〈 0.05). CONCLUSION: Inositol-1,4, 5-triphosphate (IP3)- and ryanodine-sensitive Ca^2+ stores exist in rat nociceptive trigeminal ganglion neurons. Two pathways are involved in the purinoreceptor-mediated [Ca^2+]i rise observed in nociceptive trigeminal ganglion neurons. One pathway involves the metabotropic P2Y receptors, which are associated with the IP3 sensitive Ca^2+store, and the second pathway is coupled to ionotropic P2X receptors that induce the Ca^2+ influx.
基金supported by the National Natural Science Foundation of China (Nos. 21676218, 21476185, 21472016, 21272030)the Fundamental Research Funds for the Central Universities (Nos. 2014YB027, 2452015447, 2452013py014)Shaanxi Province Science and Technology
文摘Adenosine 5'-triphosphate(ATP) not only participates in various physiological activities as the universal energy currency but also implicates in various pathological processes in living cells. Consequently,sensitive and selective detection ATP in live cells, tissues, as well as environmental samples, are urgently demanded. Due to the simple and convenient operation, economy cost, high selectivity for analyte, well biocompatibility and low cytotoxicity, fluorescent sensors for monitoring ATP have aroused great attention of researchers. In recent years, a large number of fluorescent sensors for detecting ATP have developed. This manuscript summarized most of these sensors and the interaction-mechanism between ATP and sensors, mainly including electrostatic interaction, p-p interaction, covalent bonding or hydrogen bond, or combinations of them, and the advantages of each strategy were also generalized.Here, a viewpoint of classification was shown where the sensors were divided into five typed ones according to the structure of probes used.