Postnatal development of dendritic spines on olfactory bulb granule cells in rats

In the main olfactory bulb, several populations of granule cells (GCs) can be distinguished based on the soma location either superficially, interspersed with mitral cells within the mitral cell layer (MCL), or deeper, within the GC layer (GCL). Little is known about the physiological properties of superficial GCs (sGCs) versus deep GCs (dGCs). Here, we used patch-clamp recording methods to explore the role of Group I metabotropic glutamate receptors (mGluRs) in regulating the activity of GCs in slices from wildtype and mGluR−/− mutant mice. In wildtype mice, bath application of the selective Group I mGluR agonist DHPG depolarized and increased the firing rate of both GC subtypes. In the presence of blockers of fast synaptic transmission (APV, CNQX, gabazine), DHPG directly depolarized both GC subtypes, although the two GC subtypes responded differentially to DHPG in mGluR1−/− and mGluR5−/− mice. DHPG depolarized sGCs in slices from mGluR5−/− mice, although it had no effect on sGCs in slices from mGluR1−/− mice. By contrast, DHPG depolarized dGCs in slices from mGluR1−/− mice but had no effect on dGCs in slices from mGluR5−/− mice. Previous studies showed that mitral cells express mGluR1 but not mGluR5. The present results therefore suggest that sGCs are more similar to mitral cells than dGCs in terms of mGluR expression.

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Migration of bipolar subependymal cells, precursors of the granule cells of the rat olfactory bulb, with reference to the arrangement of the radial glial fibers.

Archives of Histology and Cytology ◽

10.1679/aohc.53.219 ◽

1990 ◽

Vol 53 (2) ◽

pp. 219-226 ◽

Cited By ~ 46

Author(s):

Kiyoshi KISHI ◽

Jun Yun PENG ◽

Sachiko KAKUTA ◽

Kunio MURAKAMI ◽

Masaru KURODA ◽

...

Keyword(s):

Olfactory Bulb ◽

Granule Cells ◽

Radial Glial

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The Mitral and Short Axon Cells of the Olfactory Bulb

Journal of Cell Science ◽

10.1242/jcs.7.3.631 ◽

1970 ◽

Vol 7 (3) ◽

pp. 631-651

Author(s):

J. L. PRICE ◽

T. P. S. POWELL

Keyword(s):

Electron Microscope ◽

Olfactory Bulb ◽

Granule Cells ◽

Primary Dendrite ◽

Plexiform Layer ◽

Mitral Cell ◽

Granule Cell Layer ◽

Mitral Cells ◽

Axon Initial Segments ◽

Large Neurons

A description is given of the mitral and short axon cells of the olfactory bulb of the rat from Golgi material examined with the light microscope and from material examined with the electron microscope. The mitral cells are large neurons with primary and secondary dendrites which both extend into the overlying external plexiform layer, although only the primary dendrite enters the glomerular formations. No predominant antero-posterior orientation of the secondary dendrites has been found. Within the glomeruli the mitral cell dendrites are in synaptic contact with the olfactory nerves and also with the periglomerular cells, but elsewhere the only synapses on the mitral cells are the ‘reciprocal synapses’ with the granule cells. Synaptic-type vesicles are found in all parts of the mitral cells, including the axon initial segments; they appear to be especially concentrated in the distal portions of the dendrites. Several types of short axon cells have been found in the granule cell layer in Golgi-impregnated material. Their cell bodies can also be distinguished with the electron microscope, and from previous work it is probable that the axons of at least some of these cells form flattened-vesicle symmetrical synapses upon the granule cells.

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Differences between GABA Receptor Binding to Membranes from Cerebellum during Postnatal Development and from Cultured Cerebellar Granule Cells

Developmental Neuroscience ◽

10.1159/000112716 ◽

1982 ◽

Vol 5 (5-6) ◽

pp. 546-553 ◽

Cited By ~ 67

Author(s):

Eddi Meier ◽

Arne Schousboe

Keyword(s):

Postnatal Development ◽

Receptor Binding ◽

Gaba Receptor ◽

Granule Cells ◽

Cerebellar Granule Cells ◽

Cerebellar Granule

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Transient Activity Induces a Long-Lasting Increase in the Excitability of Olfactory Bulb Interneurons

Journal of Neurophysiology ◽

10.1152/jn.00526.2007 ◽

2008 ◽

Vol 99 (1) ◽

pp. 187-199 ◽

Cited By ~ 8

Author(s):

Tsuyoshi Inoue ◽

Ben W. Strowbridge

Keyword(s):

Olfactory Bulb ◽

Granule Cells ◽

Receptor Activation ◽

Brain Regions ◽

Persistent Activity ◽

Cellular Mechanisms ◽

Calcium Dependent ◽

Transient Activity ◽

Olfactory Bulb Slices ◽

Processing And Storage

Little is known about the cellular mechanisms that underlie the processing and storage of sensory in the mammalian olfactory system. Here we show that persistent spiking, an activity pattern associated with working memory in other brain regions, can be evoked in the olfactory bulb by stimuli that mimic physiological patterns of synaptic input. We find that brief discharges trigger persistent activity in individual interneurons that receive slow, subthreshold oscillatory input in acute rat olfactory bulb slices. A 2- to 5-Hz oscillatory input, which resembles the synaptic drive that the olfactory bulb receives during sniffing, is required to maintain persistent firing. Persistent activity depends on muscarinic receptor activation and results from interactions between calcium-dependent afterdepolarizations and low-threshold Ca spikes in granule cells. Computer simulations suggest that intrinsically generated persistent activity in granule cells can evoke correlated spiking in reciprocally connected mitral cells. The interaction between the intrinsic currents present in reciprocally connected olfactory bulb neurons constitutes a novel mechanism for synchronized firing in subpopulations of neurons during olfactory processing.

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