Expression of cyclooxygenase isoforms in the rat spinal cord and their regulation during adjuvant-induced arthritis.
OBJECTIVE
Spinal regulation of cyclooxygenase (COX) isoforms was investigated in the animal model of peripheral inflammation induced by injection of complete Freund's-type adjuvant (CFA) in the rat hindpaw.


METHODS
Peripheral inflammation was induced by intraplantar injection of CFA in one hind footpad of male Sprague Dawley rats (n = 3 per time point).


METHODS
Spinal cord was removed after different times (3 h to 22 d). mRNA and protein were isolated and analyzed by comparative reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot analysis, respectively.


RESULTS
Under the acute inflammatory stimulus 6h after CFA application, RT-PCR revealed a twofold increase in COX-2 mRNA that reached baseline again at day 3. This transient increase occurred in the lumbar spinal cord, but changes in COX-2 mRNA expression were also registered in RNA preparations from cervical sections, spinal COX-2 induction thus not being a spatially confirmed phenomenon. Western blot analysis of spinal membrane preparations reflected the transient COX-2 mRNA induction at protein levels. During the chronic phase of arthritis at day 22, COX-2 levels were again raised significantly (1.6 fold) over baseline. Spinal levels of COX-1 were not altered at any time point of the peripheral inflammation.


CONCLUSIONS
These data imply a regulatory role for COX-2 but not COX-1 in the spinal modulation under acute and chronic peripheral inflammation.
Beiche
F
F
Medizinische Klinik IV, Universität Erlangen-Nürnberg, Erlangen, Germany.
Brune
K
K
Geisslinger
G
G
Goppelt-Struebe
M
M
D000818:Animals; D001169:Arthritis, Experimental / Q000201:enzymology*; D015153:Blotting, Western; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D004487:Edema / Q000201:enzymology / Q000276:immunology; D005620:Freund's Adjuvant; D005786:Gene Expression Regulation; D007527:Isoenzymes / Q000032:analysis / Q000235:genetics*; D008161:Lumbosacral Region; D008297:Male; D008565:Membrane Proteins; D008861:Microsomes / Q000201:enzymology; D009685:Nuclear Envelope / Q000201:enzymology; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013116:Spinal Cord / Q000201:enzymology* / Q000648:ultrastructure
D007527:Isoenzymes; D008565:Membrane Proteins; D012333:RNA, Messenger; D005620:Freund's Adjuvant; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases; C496513:Ptgs1 protein, rat