Changes of COX-2 expression in the dorsal horn of the spinal cord during formalin-induced inflammatory pain and hyperalgesia in rats / 中国应用生理学杂志

ABSTRACT

<p><b>AIM</b>To observe the changes of cyclooxygenase-2 (COX-2) expression and especially the time course of the changes in dorsal horn of the spinal cord during formalin-induced inflammatory pain and hyperalgesia in rats.</p><p><b>METHODS</b>COX-2 immunohistochemistry staining was used in rat formalin pain model.</p><p><b>RESULTS</b>Compared with control group the number and immunostaining density of COX-2 immunoreactive cells in the laminae I-VI of the dorsal horn of the spinal cord increased significantly 4 h, 1 d and 3 d after formalin injection (P < 0.05). The most obvious increase was observed 1 d after the injection.</p><p><b>CONCLUSION</b>COX-2 in the dorsal horn of the spinal cord is involved in the formalin-induced inflammatory pain and hyperalgesia.</p>