title: Differential conserted activity induced regulation of Nogo receptors (1-3), LOTUS and Nogo mRNA in mouse brain.
abstract: Nogo Receptor 1 (NgR1) mRNA is downregulated in hippocampal and cortical regions by increased neuronal activity such as a kainic acid challenge or by exposing rats to running wheels. Plastic changes in cerebral cortex in response to loss of specific sensory inputs caused by spinal cord injury are also associated with downregulation of NgR1 mRNA. Here we investigate the possible regulation by neuronal activity of the homologous receptors NgR2 and NgR3 as well as the endogenous NgR1 antagonist LOTUS and the ligand Nogo. The investigated genes respond to kainic acid by gene-specific, concerted alterations of transcript levels, suggesting a role in the regulation of synaptic plasticity, Downregulation of NgR1, coupled to upregulation of the NgR1 antagonist LOTUS, paired with upregulation of NgR2 and 3 in the dentate gyrus suggest a temporary decrease of Nogo/OMgp sensitivity while CSPG and MAG sensitivity could remain. It is suggested that these activity-synchronized temporary alterations may serve to allow structural alterations at the level of local synaptic circuitry in gray matter, while maintaining white matter pathways and that subsequent upregulation of Nogo-A and NgR1 transcript levels signals the end of such a temporarily opened window of plasticity.
authors.affiliation: Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden. tobias.karlsson@ki.se
authors.forename: Tobias E
authors.initials: TE
authors.lastname: Karlsson
authors.forename: Josefin
authors.initials: J
authors.lastname: Koczy
authors.forename: Stefan
authors.initials: S
authors.lastname: Brené
authors.forename: Lars
authors.initials: L
authors.lastname: Olson
authors.forename: Anna
authors.initials: A
authors.lastname: Josephson
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism*; D005786:Gene Expression Regulation / Q000187:drug effects / Q000502:physiology*; D017403:In Situ Hybridization; D007608:Kainic Acid / Q000494:pharmacology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009185:Myelin Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000235:genetics; D000070798:Nogo Proteins; D000070817:Nogo Receptor 2; D009841:Oligonucleotides / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism*; D011956:Receptors, Cell Surface / Q000378:metabolism*
chemical_list: C583728:LOTUS protein, rat; D009185:Myelin Proteins; D009419:Nerve Tissue Proteins; D000070798:Nogo Proteins; D000070817:Nogo Receptor 2; D009841:Oligonucleotides; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; C000603201:Rtn4 protein, mouse; C000603197:Rtn4 protein, rat; C571038:Rtn4rl2 protein, mouse; D007608:Kainic Acid