PTGS2 and ischemia: These results of ours stand in harmony with the report that ischemia-related hippocampal PGE2 production in a gerbil ischemia model was potently reduced by COX-1 rather than COX-2 inhibition during the early phase of reperfusion in contrast with 24 hours later, when COX-2 appeared to be the dominant source of PGE239.