Expression and editing status of glutamate receptor GluR2 subunit in audiogenic seizure--susceptible P77PMC rats

The audiogenic seizure (AGS)-susceptible rat is a model of generalized tonic-clonic epilepsy. The inferior colliculus (IC) is established as the initiation site within the neuronal network for audiogenic seizures. Using RT-PCR, Western blot and immunocytochemistry methods, the expression of GluR2 was examined after single AGS and AGS kindling in the IC of P77PMC rat. The levels of mRNA editing of GluR2 at Q/R site were observed by restriction enzyme digest. Consequently, single AGS had no effect on the expression of GluR2 in the IC of P77PMC rat, though repetition audiogenic seizure (kindling) resulted in the decreases of GluR2 in the IC. Only complete edited form of the GluR2 at the Q/R site could be detected in single AGS and kindling. These results suggest that the decreases of the GluR2 subunit may play a role in the mechanism of AGS kindling. Alteration of the editing process of GluR2 may not be involved in AGS.