• Mol Pain · Jan 2012

    Inflammation-induced changes in BK(Ca) currents in cutaneous dorsal root ganglion neurons from the adult rat.

    • Xiu-Lin Zhang, Lee-Peng Mok, Kwan Yeop Lee, Marcel Charbonnet, and Michael S Gold.
    • Department of Anesthesiology, University of Pittsburgh, Pittsburgh, PA 15213, USA.
    • Mol Pain. 2012 Jan 1;8:37.

    BackgroundInflammation-induced sensitization of primary afferents is associated with a decrease in K(+) current. However, the type of K(+) current and basis for the decrease varies as a function of target of innervation. Because glabrous skin of the rat hindpaw is used often to assess changes in nociception in models of persistent pain, the purpose of the present study was to determine the type and extent to which K(+) currents contribute to the inflammation-induced sensitization of cutaneous afferents. Acutely dissociated retrogradely labeled cutaneous dorsal root ganglion neurons from naïve and inflamed (3 days post complete Freund's adjuvant injection) rats were studied with whole cell and perforated patch techniques.ResultsInflammation-induced sensitization of small diameter cutaneous neurons was associated with an increase in action potential duration and rate of decay of the afterhyperpolarization. However, no changes in voltage-gated K(+) currents were detected. In contrast, Ca(2+) modulated iberiotoxin sensitive and paxilline sensitive K(+) (BK(Ca)) currents were significantly smaller in small diameter IB4+ neurons. This decrease in current was not associated with a detectable change in total protein levels of the BK(Ca) channel α or β subunits. Single cell PCR analysis revealed a significant change in the pattern of expression of α subunit splice variants and β subunits that were consistent, at least in part, with inflammation-induced changes in the biophysical properties of BK(Ca) currents in cutaneous neurons.ConclusionsResults of this study provide additional support for the conclusion that it may be possible, if not necessary to selectively treat pain arising from specific body regions. Because a decrease in BK(Ca) current appears to contribute to the inflammation-induced sensitization of cutaneous afferents, BK(Ca) channel openers may be effective for the treatment of inflammatory pain.

      Pubmed     Free full text   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…