gluk2-mediated excitability within the superficial layers of the entorhinal cortexgluk2-mediated兴奋性的内表面的层内嗅皮层.pdfVIP

GluK2-Mediated Excitability within the Superficial Layers of the Entorhinal Cortex Prateep S. Beed, Benedikt Salmen, Dietmar Schmitz* ´ ¨ NeuroScience Research Center, Charite, Universitatsmedizin Berlin, Berlin, Germany Abstract Recent analysis of genetically modified mice deficient in different kainate receptor (KAR) subunits have strongly pointed to a role of the GluK2 subunit, mediating the vulnerability of the brain towards seizures. Research concerning this issue has focused mainly on the hippocampus. However, several studies point to a potential role of other parts of the hippocampal formation, in particular the entorhinal cortex, in the development of epileptic seizures. There is extensive cell death after such seizures in layer III of the medial entorhinal cortex (LIII mEC), making this region of special interest for investigation into related pathological conditions. We therefore characterized KAR mediated currents in LIII mEC pyramidal neurons by several different approaches. Using patch-clamp technique, in combination with glutamate uncaging in horizontal brain slices, we show that LIII mEC neurons exhibit KAR currents. Use of genetically modified mice reveal that these currents are mediated by GluK2 containing KARs. The IV curve indicates the predominant presence of a Ca2+ impermeable and edited form of the KAR. Finally, we show that GluK2 containing kainate receptors are essential for kainate-induced gamma oscillations within the entorhinal cortex. Citation: Beed PS, Salmen B, Schmitz D (2009) GluK2-Mediated Excitability within the Superficial Layers of the Entorhinal Cortex. PLoS ONE 4(5): e5576. doi:10.1371/journal.pone.0005576 Editor: Liset Menendez de la Prida, Instituto Cajal - CSIC, Spain Received January 8, 2009; Accepted April 13, 2009; Published May 18, 2009 Copyri