Frontal cortex and hippocampus neurotransmitter receptor complex level parallels spatial memory performance in the radial arm maze.
Several neurotransmitter receptors have been proposed to be involved in memory formation. However, information on receptor complexes (RCs) in the radial arm maze (RAM) is missing. It was therefore the aim of this study to determine major neurotransmitter RCs levels that are modulated by RAM training because receptors are known to work in homo-or heteromeric assemblies. Immediate early gene Arc expression was determined by immunohistochemistry to show if prefrontal cortices (PFC) and hippocampi were activated following RAM training as these regions are known to be mainly implicated in spatial memory. Twelve rats per group, trained and untrained in the twelve arm RAM were used, frontal cortices and hippocampi were taken, RCs in membrane protein were quantified by blue-native PAGE immunoblotting. RCs components were characterised by co-immunoprecipitation followed by mass spectrometrical analysis and by the use of the proximity ligation assay. Arc expression was significantly higher in PFC of trained as compared to untrained rats whereas it was comparable in hippocampi. Frontal cortical levels of RCs containing AMPA receptors GluA1, GluA2, NMDA receptors GluN1 and GluN2A, dopamine receptor D1, acetylcholine nicotinic receptor alpha 7 (nAChR-α7) and hippocampal levels of RCs containing D1, GluN1, GluN2B and nAChR-α7 were increased in the trained group; phosphorylated dopamine transporter levels were decreased in the trained group. D1 and GluN1 receptors were shown to be in the same complex. Taken together, distinct RCs were paralleling performance in the RAM which is relevant for interpretation of previous and design of future work on RCs in memory studies.
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria.
Bharanidharan
B
Shanmugasundaram
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria.
Ajinkya
A
Sase
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria.
András G
AG
Miklosi
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria; CeMM Research Center for Molecular Medicine of the Austrian Academy of Science, Lazarettgasse 14, AKH BT 25.3, A-1090 Vienna, Austria.
Fernando J
FJ
Sialana
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria.
Saraswathi
S
Subramaniyan
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria.
Yogesh D
YD
Aher
Core Facility, Medical University of Vienna, Lazarettegasse 14, A-1090 Vienna, Austria.
Marion
M
Gröger
Core Unit of Biomedical Research, Division of Laboratory Animal Science and Genetics, Medical University of Vienna, Brauhausgasse 34, A-2325 Himberg, Austria.
Harald
H
Höger
CeMM Research Center for Molecular Medicine of the Austrian Academy of Science, Lazarettgasse 14, AKH BT 25.3, A-1090 Vienna, Austria.
Keiryn L
KL
Bennett
Department of Pediatrics, Medical University of Vienna, Währinger Gürtel 18, 1090 Vienna, Austria. Electronic address: gert.lubec@meduniwien.ac.at.
Gert
G
Lubec
D000818:Animals; D003598:Cytoskeletal Proteins / Q000378:metabolism; D005625:Frontal Lobe / Q000378:metabolism*; D017781:Genes, Immediate-Early; D006624:Hippocampus / Q000378:metabolism*; D008297:Male; D018782:Maze Learning / Q000502:physiology; D009419:Nerve Tissue Proteins / Q000378:metabolism; D021122:Protein Subunits / Q000032:analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D018091:Receptors, AMPA / Q000032:analysis; D017447:Receptors, Dopamine D1 / Q000032:analysis; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis; D017981:Receptors, Neurotransmitter / Q000032:analysis*; D011978:Receptors, Nicotinic / Q000032:analysis; D065852:Spatial Memory / Q000502:physiology*
D003598:Cytoskeletal Proteins; D009419:Nerve Tissue Proteins; D021122:Protein Subunits; D018091:Receptors, AMPA; D017447:Receptors, Dopamine D1; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D011978:Receptors, Nicotinic; C092069:activity regulated cytoskeletal-associated protein
Blue native PAGE; D1-GluN1 complex; Neurotransmitter receptor complex; Radial arm maze; Spatial memory