Subunit composition of kainate receptors in hippocampal interneurons.
Kainate receptor activation affects GABAergic inhibition in the hippocampus by mechanisms that are thought to involve the GluR5 subunit. We report that disruption of the GluR5 subunit gene does not cause the loss of functional KARs in CA1 interneurons, nor does it prevent kainate-induced inhibition of evoked GABAergic synaptic transmission onto CA1 pyramidal cells. However, KAR function is abolished in mice lacking both GluR5 and GluR6 subunits, indicating that KARs in CA1 stratum radiatum interneurons are heteromeric receptors composed of both subunits. In addition, we show the presence of presynaptic KARs comprising the GluR6 but not the GluR5 subunit that modulate synaptic transmission between inhibitory interneurons. The existence of two separate populations of KARs in hippocampal interneurons adds to the complexity of KAR localization and function.
Mulle
C
C
Centre National de la Recherche Scientifique, UMR 5091, Institut Françios Magendie, Université Bordeaux 2, France. mulle@u-bordeaux2.fr
Sailer
A
A
Swanson
G T
GT
Brana
C
C
O'Gorman
S
S
Bettler
B
B
Heinemann
S F
SF
D000818:Animals; D002478:Cells, Cultured; D003433:Crosses, Genetic; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation / Q000187:drug effects; D018691:Excitatory Amino Acid Antagonists; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007395:Interneurons / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D007608:Kainic Acid / Q000378:metabolism / Q000494:pharmacology; D051379:Mice; D008815:Mice, Inbred Strains; D018345:Mice, Knockout; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D009467:Neuromuscular Depolarizing Agents / Q000494:pharmacology; D009475:Neurons, Afferent / Q000187:drug effects / Q000378:metabolism; D018408:Patch-Clamp Techniques; D021122:Protein Subunits; D017966:Pyramidal Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors; D018092:Kainic Acid Receptors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D013779:Tetrodotoxin / Q000494:pharmacology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism; D000097806:GluK2 Kainate Receptor
D018691:Excitatory Amino Acid Antagonists; D007608:Kainic Acid; D009467:Neuromuscular Depolarizing Agents; D021122:Protein Subunits; D018091:Receptors, AMPA; D018092:Kainic Acid Receptors; D013779:Tetrodotoxin; D005680:gamma-Aminobutyric Acid; D000097806:GluK2 Kainate Receptor