title: Olfactory bulb interneurons releasing NO exhibit the Reelin receptor ApoEr2 and part of those targeted by NO express Reelin.
abstract: Nitric oxide (NO) and Reelin both modulate neuronal plasticity in developing and mature synaptic networks. We recently showed a loss of neuronal nitric oxide synthase (nNOS) protein in the olfactory bulb of reeler mutants and advanced the hypothesis that the Reelin and NO signalling pathways may influence each other. We now studied the distribution of NO sensitive guanylyl cyclase (NOsGC), Reelin and its receptor Apolipoprotein E2 (ApoEr2) in the olfactory bulb by multiple fluorescence labelling and tested whether nNOS and ApoEr2 colocalize in this area. We also essayed the protein content of NOsGC in the reeler olfactory bulb and tested whether there are any changes in nNOS and NOsGC protein in other reeler brain areas. Olfactory bulb interneurons expressing ApoEr2 and nNOS are only few in the glomerular layer but represent the large majority of granule cell layer interneurons. Conversely, NOsGC interneurons are rare in the granule cell layer and abundant as periglomerular cells. Reelin containing periglomerular cells almost entirely belong to the NOsGC subset. These data further support the hypothesis of a reciprocal signalling between Reelin/NOsGC and ApoEr2/nNOS expressing neurons to affect olfactory bulb activity. We also show that a significant rise in NOsGC content accompanies the decrease of nNOS protein in the reeler olfactory bulb. The same reciprocal changes present in the cortex/striatum and the hippocampus of reeler mice. Thus, the influence that the deficit of extracellular Reelin seems to exert on nNOS and its receptor is not limited to the olfactory bulb but is a general feature of the reeler brain.
authors.affiliation: Department of Anatomy, University of Bern, CH3012 Bern, Switzerland.
authors.forename: Gudrun
authors.initials: G
authors.lastname: Herrmann
authors.forename: Georgi
authors.initials: G
authors.lastname: Mishev
authors.forename: Alessandra L
authors.initials: AL
authors.lastname: Scotti
mesh_terms: D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000166:cytology; D001923:Brain Chemistry / Q000235:genetics / Q000502:physiology; D064032:Calbindin 2; D064026:Calbindins; D015816:Cell Adhesion Molecules, Neuronal / Q000096:biosynthesis* / Q000235:genetics; D016326:Extracellular Matrix Proteins / Q000096:biosynthesis* / Q000235:genetics; D006162:Guanylate Cyclase / Q000378:metabolism; D007150:Immunohistochemistry; D007395:Interneurons / Q000502:physiology*; D007606:Juxtaglomerular Apparatus / Q000378:metabolism; D026502:LDL-Receptor Related Proteins; D051379:Mice; D008818:Mice, Neurologic Mutants; D018613:Microscopy, Confocal; D009419:Nerve Tissue Proteins / Q000096:biosynthesis* / Q000235:genetics; D009569:Nitric Oxide / Q000378:metabolism* / Q000502:physiology*; D052248:Nitric Oxide Synthase Type I / Q000096:biosynthesis; D009830:Olfactory Bulb / Q000166:cytology* / Q000502:physiology*; D011956:Receptors, Cell Surface / Q000096:biosynthesis* / Q000235:genetics; D018110:Receptors, Lipoprotein / Q000096:biosynthesis* / Q000235:genetics; D000091042:Reelin Protein; D064030:S100 Calcium Binding Protein G / Q000096:biosynthesis; D012697:Serine Endopeptidases / Q000096:biosynthesis* / Q000235:genetics
chemical_list: D064032:Calbindin 2; D064026:Calbindins; D015816:Cell Adhesion Molecules, Neuronal; D016326:Extracellular Matrix Proteins; D026502:LDL-Receptor Related Proteins; D009419:Nerve Tissue Proteins; D011956:Receptors, Cell Surface; D018110:Receptors, Lipoprotein; D000091042:Reelin Protein; D064030:S100 Calcium Binding Protein G; C098773:low density lipoprotein receptor-related protein 8; C469363:reelin receptor; D009569:Nitric Oxide; D052248:Nitric Oxide Synthase Type I; C000717128:Reln protein, mouse; D012697:Serine Endopeptidases; D006162:Guanylate Cyclase