TY - JOUR
T1 - Inflammation-induced changes in peripheral glutamate receptor populations
AU - Carlton, S. M.
AU - Coggeshall, R. E.
N1 - Funding Information:
The authors thank Brenda Kenworthy for her excellent secretarial assistance, Zhixia Ding for assistance with the immunohistochemistry and electron microscopy and Greg Hargett for his contribution to the behavioral studies. This work was supported by NIH NS11255 to S.M.C. and R.E.C., NS27910 to S.M.C and NS10161 to R.E.C.
PY - 1999/2/27
Y1 - 1999/2/27
N2 - The ionotropic glutamate receptors N-methyl-D-aspartate (NMDA), α- amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate (KA) have been localized on subpopulations of unmyelinated and myelinated sensory axons in normal skin. Behavioral studies indicate that activation of these receptors results in nociceptive behaviors and contributes to inflammatory pain. The goal of the present study was to determine if these glutamate receptors might contribute to the peripheral hypersensitivity observed in inflammation. The major findings were that 48 h following complete Freund's adjuvant (CFA)-induced inflammation, the proportions of unmyelinated axons labeled for NMDA, AMPA or KA receptors were 61%, 43% and 48%, respectively, in cutaneous nerves in the inflamed paw compared to 48%, 22% and 27%, respectively, in the non-inflamed paw. The proportions of myelinated axons labeled for NMDA, AMPA or KA receptors were 61%, 61% and 43%, respectively, compared to 43%, 42% and 28%, respectively, in the non-inflamed hindpaw. These increases were all significant. These data indicate that the number of sensory axons containing ionotropic glutamate receptors increases during inflammation, and this may be a contributing factor to peripheral sensitization in inflammation.
AB - The ionotropic glutamate receptors N-methyl-D-aspartate (NMDA), α- amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) and kainate (KA) have been localized on subpopulations of unmyelinated and myelinated sensory axons in normal skin. Behavioral studies indicate that activation of these receptors results in nociceptive behaviors and contributes to inflammatory pain. The goal of the present study was to determine if these glutamate receptors might contribute to the peripheral hypersensitivity observed in inflammation. The major findings were that 48 h following complete Freund's adjuvant (CFA)-induced inflammation, the proportions of unmyelinated axons labeled for NMDA, AMPA or KA receptors were 61%, 43% and 48%, respectively, in cutaneous nerves in the inflamed paw compared to 48%, 22% and 27%, respectively, in the non-inflamed paw. The proportions of myelinated axons labeled for NMDA, AMPA or KA receptors were 61%, 61% and 43%, respectively, compared to 43%, 42% and 28%, respectively, in the non-inflamed hindpaw. These increases were all significant. These data indicate that the number of sensory axons containing ionotropic glutamate receptors increases during inflammation, and this may be a contributing factor to peripheral sensitization in inflammation.
KW - Immunohistochemistry
KW - Nociception
KW - Primary afferents
KW - Sensory neurons
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U2 - 10.1016/S0006-8993(98)01328-6
DO - 10.1016/S0006-8993(98)01328-6
M3 - Article
C2 - 10023031
AN - SCOPUS:0033608399
SN - 0006-8993
VL - 820
SP - 63
EP - 70
JO - Brain Research
JF - Brain Research
IS - 1-2
ER -