Prostaglandin (PG) F2α is one of the major prostanoids biosynthesized by cyclooxygenases (COXs) from arachidonic acid. Although it has been reported that there is a selective surge in PGF2α production in the hippocampus during kainic acid (KA)-induced seizure activity, the precise intra-hippocampal distribution of PGF2α has not been elucidated due to the paucity of effective histological techniques for detecting PGs in tissues. We investigated the tissue distribution of PGF2α in the rat hippocampus 30min after KA injection by developing fixation and immunohistological-staining methods. To detect PGF2α directly on histological sections, we used systemic perfusion fixation with water-soluble carbodiimide fixative, followed by immersion of the brains in Zamboni's fixative. We then performed immunofluorescence staining with anti-PGF2α antibody, with negative control experiments used to confirm the staining specificity. Definitive immunolabeling for PGF2α was evident most markedly in pyramidal cells of the hippocampal cornu Ammonis (CA) 3 sector and neurons of the hilus in KA-treated rats. Immunolabeling for PGF2α was also evident in granule cells of the dentate gyrus. Double immunfluorescence staining revealed that PGF2α-immunopositive neurons expressed cytosolic phospholipases A2, COX-2, and FP receptor. These results suggest that the major source of PGF2α production immediately after KA injection was neurons of the hippocampal CA3 sector, hilus and dentate gyrus. These neurons exert PGF2α-mediated functions via FP receptors in an autocrine/paracrine manner and may play pathophysiological roles in the acute phase (30min) of excitotoxicity.
|Original language||English (US)|
|Number of pages||10|
|State||Published - Aug 30 2012|
All Science Journal Classification (ASJC) codes