Role of prostacyclin in the development of compression trauma-induced spinal cord injury in rats.

We investigated the role of prostacyclin (PGI2) in the development of compression trauma–induced spinal cord injury (SCI) in rats. When measured after induction of SCI, tissue levels of 6-keto-PGF1α, a stable PGI2 metabolite, thromboxane B2 (TXB2), a stable metabolite of thromboxane A2, myeloperoxidase (MPO) activity, and tumor necrosis factor (TNF) in the injured spinal cord segment were significantly increased, peaking at 2, 3, and 4 h after induction of SCI, respectively. Subcutaneous administration of indomethacin (IM), a non-selective cyclooxygenase (COX) inhibitor, completely inhibited increases in tissue levels of 6-keto-PGF1α and TXB2, while administration of NS-398, a selective inhibitor of COX-2, did not affect these increases. Although pretreatment with IM enhanced increases in tissue levels of MPO, TNF, and TNF mRNA and exacerbated both motor disturbances and histological damage in the spinal cord of animals subjected to SCI, pretreatment with NS-398 had no effect on any of these findings. Bot...