|
|
||||||||
Published online before print March 7, 2006
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Article |
Klinik für Anaesthesiologie und operative Intensivmedizin, Charité-Universitätsmedizin Berlin, Campus Benjamin Franklin, Germany
@ To whom correspondence should be addressed. E-mail: alexander.brack{at}charite.de.
| Abstract |
|---|
Polymorphonuclear cells (PMN) are recruited in early inflammation and are believed to contribute to inflammatory pain. However, studies demonstrating a hyperalgesic role of PMN did not examine selective PMN recruitment or did not document effective PMN recruitment. We hypothesized that hyperalgesia does not develop after chemokine-induced PMN selective recruitment and is independent of PMN infiltration in complete Freunds adjuvant (CFA)-induced, local inflammation. PMN were recruited by intraplantar injection of CXC chemokine ligand 1 (CXCL1; keratinocyte-derived chemokine), CXCL2/3 (macrophage inflammatory protein-2), or CFA, with or without preceding systemic PMN depletion. Chemokine inoculation resulted in dose (0-30 µg)- and time (0-12 h)-dependent, selective recruitment of PMN as quantified by flow cytometry. CXCL2/3, but not CXCL1, was less effective at high doses, probably as a result of significant down-regulation of CXC chemokine receptor 2 expression on blood PMN. Neither chemokine caused mechanical or thermal hyperalgesia as determined by the Randall-Selitto and Hargreaves test, respectively, despite comparable expression of activation markers (i.e., CD11b, CD18, and L-selectin) on infiltrating PMN. In contrast, CFA injection induced hyperalgesia, independent of PMN recruitment. c-Fos mRNA and immunoreactivity in the spinal cord were increased significantly after inoculation of CFA, independent of PMN migration but not of CXCL2/3. Measurement of potential hyperalgesic mediators showed that hyperalgesia correlated with local prostaglandin E2 (PGE2) but not with interleukin-1
production. In summary, hyperalgesia, local PGE2 production, and spinal c-Fos expression occur after CFA-induced inflammation but not after CXCL1- or CXCL2/3-induced, selective PMN recruitment. Thus, PMN seem to be less important in inflammatory hyperalgesia than previously thought.
Key Words: chemokine CXCR2 neutrophil hyperalgesia complete Freund’s adjuvant
Related Articles
This article has been cited by other articles:
![]() |
T. M. Cunha, W. A. Verri Jr., I. R. Schivo, M. H. Napimoga, C. A. Parada, S. Poole, M. M. Teixeira, S. H. Ferreira, and F. Q. Cunha Crucial role of neutrophils in the development of mechanical inflammatory hypernociception J. Leukoc. Biol., April 1, 2008; 83(4): 824 - 832. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A Mousa, R. H Straub, M. Schafer, and C. Stein {beta}-Endorphin, Met-enkephalin and corresponding opioid receptors within synovium of patients with joint trauma, osteoarthritis and rheumatoid arthritis Ann Rheum Dis, July 1, 2007; 66(7): 871 - 879. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. L. Rittner, D. Labuz, M. Schaefer, S. A. Mousa, S. Schulz, M. Schafer, C. Stein, and A. Brack Pain control by CXCR2 ligands through Ca2+-regulated release of opioid peptides from polymorphonuclear cells FASEB J, December 1, 2006; 20(14): 2627 - 2629. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. L. Rittner, H. Machelska, M. Schafer, C. Stein, and A. Brack Comment on "Neutrophils: are they hyperalgesic or anti-hyperalgesic?" J. Leukoc. Biol., October 1, 2006; 80(4): 729 - 730. [Full Text] [PDF] |
||||
![]() |
T. M. Cunha and W. A. Verri Jr Neutrophils: are they hyperalgesic or anti-hyperalgesic? J. Leukoc. Biol., October 1, 2006; 80(4): 727 - 728. [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |