P2X7 receptor regulates leukocyte infiltrations in rat frontoparietal cortex following status epilepticus

Background: in the present study,we investigated the roles of p2x7 receptor in recruitment and infiltration of neutrophil during epileptogenesis in rat epilepsy models.methods: status epilepticus (se) was induced by pilocarpine in rats that were intracerebroventricularly infused with either saline,2',3'-o-(4-benzoylbenzoyl)-adenosine 5'-triphosphate (bzatp),adenosine 5'-triphosphate-2',3'-dialdehyde (oxatp),or il-1ra (interleukin 1 receptor antagonist) prior to se induction. thereafter,we performed immunohistochemical studies for myeloperoxidase (mpo),cd68,interleukin-1β (il-1β),monocyte chemotactic protein-1 (mcp-1) and macrophage inflammatory protein-2 (mip-2).results: in saline-infused animals,neutrophils and monocytes were observed in frontoparietal cortex (fpc) at 1 day and 2 days after se,respectively. in bzatp-infused animals,infiltrations of neutrophils and monocytes into the fpc were detected at 12 hr and 1 day after se,respectively. in oxatp-infused animals,neutrophils and monocytes infiltrated into the fpc at 1 day and 2 days after se,respectively. however,the numbers of both classes of leukocytes were significantly lower than those observed in the saline-infused group. in piriform cortex (pc),massive leukocyte infiltration was detected in layers iii/iv of saline-infused animals at 1-4 days after induction of se. bzatp or oxatp infusion did not affect neutrophil infiltration in the pc. in addition,p2x7 receptor-mediated mcp-1 (released from microglia)/mip-2 (released from astrocytes) regulation was related to se-induced leukocyte infiltration in an il-1β-independent manner.conclusions: our findings suggest that selective regulation of p2x7 receptor-mediated neutrophil infiltration may provide new therapeutic approaches to se or epilepsy. © 2010 kim et al; licensee biomed central ltd.