• J. Pharmacol. Sci. · Feb 2004

    Review

    ATP- and adenosine-mediated signaling in the central nervous system: chronic pain and microglia: involvement of the ATP receptor P2X4.

    • Kazuhide Inoue, Makoto Tsuda, and Schuichi Koizumi.
    • Division of Biosignaling, National Institute of Health Sciences, Tokyo, Japan. inoue@nihs.go.jp
    • J. Pharmacol. Sci. 2004 Feb 1;94(2):112-4.

    AbstractWe have been studying the role of ATP receptors in pain and already reported that activation of P2X(2/3) heteromeric channel/receptor in primary sensory neurons causes acutely tactile allodynia, one hallmark of neuropathic pain. We report here that tactile allodynia under the chronic pain state requires an activation of the P2X(4) ionotropic ATP receptor and p38 mitogen-activated protein kinase (MAPK) in spinal cord microglia. Two weeks after L5 spinal nerve injury, rats displayed a marked mechanical allodynia. In the rats, activated microglia were detected in the injured side of the dorsal horn and the level of the dually-phosphorylated active form of p38MAPK (phospho-p38MAPK) in these microglia was increased. Moreover, intraspinal administration of a p38MAPK inhibitor, SB203580, suppressed the allodynia. We also found that the expression level of P2X(4) was increased strikingly in spinal cord microgila after nerve injury and that pharmacological blockade or inhibition of the expression of P2X(4) reversed the allodynia. Taken together, our results demonstrate that activation of P2X(4) or p38MAPK in spinal cord microglia is necessary for tactile allodynia after nerve injury.

      Pubmed     Copy Citation     Plaintext  

      Add institutional full text...

    Notes

     
    Knowledge, pearl, summary or comment to share?
    300 characters remaining
    help        
    You can also include formatting, links, images and footnotes in your notes
    • Simple formatting can be added to notes, such as *italics*, _underline_ or **bold**.
    • Superscript can be denoted by <sup>text</sup> and subscript <sub>text</sub>.
    • Numbered or bulleted lists can be created using either numbered lines 1. 2. 3., hyphens - or asterisks *.
    • Links can be included with: [my link to pubmed](http://pubmed.com)
    • Images can be included with: ![alt text](https://bestmedicaljournal.com/study_graph.jpg "Image Title Text")
    • For footnotes use [^1](This is a footnote.) inline.
    • Or use an inline reference [^1] to refer to a longer footnote elseweher in the document [^1]: This is a long footnote..

    hide…