TY - JOUR T1 - Cyclooxygenase-2 Contributes to<em>N</em>-Methyl-<span class="sc">d</span>-aspartate-Mediated Neuronal Cell Death in Primary Cortical Cell Culture JF - Journal of Pharmacology and Experimental Therapeutics JO - J Pharmacol Exp Ther SP - 417 LP - 425 VL - 293 IS - 2 AU - Sandra J. Hewett AU - Tracy F. Uliasz AU - Aniruddha S. Vidwans AU - James A. Hewett Y1 - 2000/05/01 UR - http://jpet.aspetjournals.org/content/293/2/417.abstract N2 - Cyclooxygenase isozymes (COX-1 and COX-2) are found to be constitutively expressed in brain, with neuronal expression of COX-2 being rapidly induced after numerous insults, including cerebral ischemia. Because overactivation ofN-methyl-d-aspartate (NMDA) receptors has been implicated in the cell loss associated with ischemia, we characterized the expression of the COX isozymes in murine mixed cortical cell cultures and used isozyme-selective inhibitors to determine their relative contribution to NMDA receptor-stimulated prostaglandin (PG) production and excitotoxic neuronal cell death. Immunocytochemical analysis of mixed cortical cell cultures revealed that COX-2 expression was restricted to neurons, whereas COX-1 was expressed in both neurons and astrocytes. Brief exposure to NMDA (5 min; 100 μM) elicited a time-dependent accumulation of PGs in the culture medium that preceded neuronal cell death and correlated with the induction of COX-2 mRNA. COX-1 expression remained unchanged. Flurbiprofen, a nonselective COX-1/COX-2 inhibitor, blocked NMDA-stimulated PG production and attenuated neuronal death in a concentration-dependent manner. Similar results were obtained with the specific COX-2 inhibitor NS-398 (10–30 μM) but not with the selective COX-1 inhibitor valeryl salicylate (10–300 μM). Inhibition of total constitutive COX activity with aspirin (100 μM, 1.5 h) before NMDA exposure did not prevent subsequent NMDA-mediated neuronal cell death. However, neuronal injury in aspirin-pretreated cultures was attenuated by flurbiprofen administration after NMDA exposure. Finally, the protection afforded by COX-2 inhibition was specific for NMDA because neither flurbiprofen nor NS-398 protected neurons against kainate-mediated neurotoxicity. Together, these results support the conclusion that newly synthesized COX-2 protein contributes to NMDA-induced neuronal injury. The American Society for Pharmacology and Experimental Therapeutics ER -