title: AGS-induced expression of Narp is concomitant with expression of AMPA receptor subunits GluR1 and GluR2 in hippocampus but not inferior colliculus of P77PMC rats.
abstract: To explore mechanisms of epileptogenesis in audiogenic seizures (AGS), we examined the expression of alpha-amino-3-hydroxy-5-methyl-4-isoxazoleopropionic acid (AMPA) receptor subunits GluR1 and GluR2 and of the GluR-associated protein Narp in the hippocampus and the inferior colliculus (IC) from AGS-susceptible P77PMC rats after a single AGS and audiogenic kindling. Western blotting and immunohistochemistry showed that Narp was rapidly induced in both the hippocampus and the IC by AGS. In the hippocampus, up-regulation of Narp was concomitant with GluR1 and GluR2 under both conditions of a single AGS and AGS kindling. In the IC, however, Narp was up-regulated, GluR2 down-regulated, and GluR1 unchanged after kindling. In comparison with kindling, neither GluR1 nor GluR2 was changed, while Narp significantly increased in the IC following a single AGS. These findings suggest that down-regulation of AMPA receptor GluR2 subunit in the IC may contribute to AGS-mediated epileptogenesis, and up-regulation of Narp in the IC may be involved in audiogenic seizures.
authors.affiliation: Department of Biochemistry and Molecular Biology, Peking University Health Science Center, 100083, Beijing, People's Republic of China.
authors.forename: Shu-Yan
authors.initials: SY
authors.lastname: Li
authors.forename: De-Sheng
authors.initials: DS
authors.lastname: Xu
authors.forename: Hong-Ti
authors.initials: HT
authors.lastname: Jia
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D002097:C-Reactive Protein / Q000378:metabolism*; D015536:Down-Regulation / Q000502:physiology; D020195:Epilepsy, Reflex / Q000235:genetics / Q000378:metabolism* / Q000503:physiopathology; D005260:Female; D018698:Glutamic Acid / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism* / Q000503:physiopathology; D007245:Inferior Colliculi / Q000378:metabolism* / Q000503:physiopathology; D007696:Kindling, Neurologic / Q000502:physiology; D008297:Male; D009419:Nerve Tissue Proteins / Q000378:metabolism*; D051381:Rats; D011922:Rats, Mutant Strains; D018091:Receptors, AMPA / Q000378:metabolism*; D009435:Synaptic Transmission / Q000502:physiology; D015854:Up-Regulation / Q000502:physiology; D000099153:Pentraxins
chemical_list: D002097:C-Reactive Protein; D018698:Glutamic Acid; D009419:Nerve Tissue Proteins; D018091:Receptors, AMPA; D000099153:Pentraxins; C104722:glutamate receptor ionotropic, AMPA 2