PTGS2 and stroke disorder: Continuous injection of NPD1 into the fourth ventricle (400 ng/48 h) after ischemic experimental stroke reduced stroke size in rats by 50% (28, 29), attenuated polymorphonuclear leukocyte infiltration, and inhibited ischemia induction of cyclooxygenase-2 (COX-2) and nuclear factor κB (NF-κB) (18, 28).