NR2B RECEPTOR EXPRESSION IN RAT CNS IN 3-MERCAPTOPROPIONIC ACID –INDUCED EXPERIMENTAL EPILEPSY

GIRARDI E; AUZMENDI J; CHARÓ N; PICHEL M; GONZÁLEZ N

Montevideo, Uruguay

Congreso; 5º Congreso Latinoamericano de Epilepsia.; 2008

La Liga Internacional contra la Epilepsia (ILAE) y el Buró Internacional para la Epilepsia (IBE)

NMDA receptor participate in the initiation and/or propagation of epileptiform discharges, this receptor is an heteromeric complex composed of NR1subunit and different NR2 subunits that determine different functional properties. In our laboratory we have studied NR2B expression in hippocampus and cerebellum in 3-mercaptopropionic acid–induced experimental epilepsy. Methods: Lots of Wistar rats (250-300g) were daily injected with MP, 45mg/kg, i.p., during 4 days (MP4) and 7days (MP7). Rats injected with saline were used as control. Hippocampus and cerebellum were processed for immunohistochemical assays using antiNR2B antibody and peroxidase- antiperoxidase techniques. Results are expressed in relative optical density and analized by ANOVA one way and Student-Newman-Keuls test. Results: Inmunohistochemical studies showed a decreased expression in NR2B in CA1 and CA2/3 oriens stratum, pyramidal cell layer, radiatum and lacunosum molecular (21-73%) after MP4. At MP7 a reversion response was observed in CA1, CA2/3 stratum oriens, pyramidal cells layer and in CA1stratum radiatum. In Dentate gyrus granulare layer decreased immunostaining (20%) and in hillus (71%), while in subicullum (63%). These decreases were maintained at MP7. In cerebellum positive Purkinje cells were observed and a decreaase (50%) at MP4 and 10% at MP 7 was determined. Conclusions: These results suggest that NR2B participate modulating seizure activity in hippocampus and cerebellum in MP-induce epileptic model.