Afferent and efferent nerve endings of the outer hair cells in the rahbit

Omata, Takeo; Schätzle, W.

doi:10.1007/bf02565519

Cited by 10 publications

(7 citation statements)

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“…Additionally, it has been shown that myelinated axons are more vulnerable to hypoxic stress than unmyelinated axons (Waxman et al, 1991). Studies employing immersion fixation or delaying fixation of tissue until lengthy dissections are completed seem more likely to encounter MVBs in axons (Chu-Wang and Oppenheim, 1980; Omata and Schatzle, 1980; Schmied and Holtzman, 1987; Sandow et al, 2000). Additionally, many of the studies that report MVBs in myelinated axons introduced exogenous proteins, i.e.…”

Section: Discussionmentioning

confidence: 99%

Quantitative analysis of multivesicular bodies (MVBs) in the hypoglossal nerve: Evidence that neurotrophic factors do not use MVBs for retrograde axonal transport

Altick

Baryshnikova

et al. 2009

J of Comparative Neurology

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Multivesicular bodies (MVBs) are defined by multiple internal vesicles enclosed within an outer, limiting membrane. MVBs have previously been quantified in neuronal cell bodies and in dendrites, but their frequencies and significance in axons are controversial. Despite lack of conclusive evidence, it is widely believed that MVBs are the primary organelle that carries neurotrophic factors in axons. Reliable information about axonal MVBs under physiological and pathological conditions is needed for a realistic assessment of their functional roles in neurons. We provide a quantitative ultrastructural analysis of MVBs in the normal postnatal rat hypoglossal nerve and under a variety of experimental conditions. MVBs were about 50 times less frequent in axons than in neuronal cell bodies or dendrites. Five distinct types of MVBs were distinguished in axons, based on MVB size, electron density and size of internal vesicles. While target manipulations did not significantly change MVBs in axons, dystrophic conditions such as delayed fixation substantially increased the number of axonal MVBs. Radiolabeled brain-and glial-cell derived neurotrophic factors (BDNF and GDNF) injected into the tongue did not accumulate during retrograde axonal transport in MVBs, as determined by quantitative ultrastructural autoradiography, and confirmed by analysis of quantum dot-labeled BDNF. We conclude that for axonal transport, neurotrophic factors utilize small vesicles or endosomes that can be inconspicuous at transmission electron microscopic resolution, rather than MVBs. Previous reports of axonal MVBs may be based, in part, on artificial generation of such organelles in axons due to dystrophic conditions.

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Section: Discussionmentioning

confidence: 99%

Quantitative analysis of multivesicular bodies (MVBs) in the hypoglossal nerve: Evidence that neurotrophic factors do not use MVBs for retrograde axonal transport

Altick

Baryshnikova

et al. 2009

J of Comparative Neurology

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“…MVBs have also been noted among the afferent and efferent innervation of outer hair cells within the mammalian inner ear (Omata and Schatzle, 1980) and in cardiac ganglion terminals (Pauziene and Pauza, 2003). Presently, the function of MVBs at these locations is unknown and largely unexamined.…”

Section: Distribution Of Mvbs In Neuronal Compartmentsmentioning

confidence: 99%

“…In some studies (Chu-Wang and Oppenheim, 1980, Omata and Schatzle, 1980; Pauziene and Pauza, 2003), the tissues were not immediately fixed. Delays of up to 8 hours (and lack of oxygen during this delay) could have rendered the terminals ischemic or dystrophic.…”

Section: Distribution Of Mvbs In Neuronal Compartmentsmentioning

confidence: 99%

Multivesicular bodies in neurons: Distribution, protein content, and trafficking functions

Bartheld

Altick

2011

Progress in Neurobiology

176

157

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SummaryMultivesicular bodies (MVBs) are intracellular endosomal organelles characterized by multiple internal vesicles that are enclosed within a single outer membrane. MVBs were initially regarded as purely prelysosomal structures along the degradative endosomal pathway of internalized proteins. MVBs are now known to be involved in numerous endocytic and trafficking functions, including protein sorting, recycling, transport, storage, and release. This review of neuronal MVBs summarizes their research history, morphology, distribution, accumulation of cargo and constitutive proteins, transport, and theories of functions of MVBs in neurons and glia. Due to their complex morphologies, neurons have expanded trafficking and signaling needs, beyond those of "geometrically simpler" cells, but it is not known whether neuronal MVBs perform additional transport and signaling functions. This review examines the concept of compartment-specific MVB functions in endosomal protein trafficking and signaling within synapses, axons, dendrites and cell bodies. We critically evaluate reports of the accumulation of neuronal MVBs based on evidence of stress-induced MVB formation. Furthermore, we discuss potential functions of neuronal and glial MVBs in development, in dystrophic neuritic syndromes, injury, disease, and aging. MVBs may play a role in Alzheimer's, Huntington's, and Niemann-Pick diseases, some types of frontotemporal dementia, prion and virus trafficking, as well as in adaptive responses of neurons to trauma and toxin or drug exposure. Functions of MVBs in neurons have been much neglected, and major gaps in knowledge currently exist. Developing truly MVB-specific markers would help to elucidate the roles of neuronal MVBs in intra-and intercellular signaling of normal and diseased neurons. KeywordsEndosome; Trafficking; Axonal Transport; Sorting; Release; Endocytosis; Degradation Definition of MVBs and scope of this reviewBased on their original discovery and historical tradition, MVBs are defined -as their name implies -by morphological criteria at the ultrastructural level. MVBs appear in ultrathin sections as spherical organelles characterized by a single outer ("limiting") membrane that Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Cooney et al., 2002). The small vesicles as well as the matrix, the lumenal space between the internal vesicles, are typically clear, but they can be of varying electron densities (Roizin et al., 1967). The internal vesicles can have heterogeneous sizes with a diameter of 50-100 nm, although they frequently are uniform in size, about 60-70 nm in...

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“…Since then, the fine structure of hair cell receptoneural junctions (hair cell synapses) has been studied by many researchers in an attempt to characterize the structure and function of hair cells in the sensory epithelium of the acousticolateralis organs (Ades and Engstrom, 1974;Bodian, 1978Bodian, , 1980Bredberg, 1977;Engstrom, 1967a,b;Engstrom and Sjostrand, 1954;Iurato, 1961Iurato, , 1967Kimura, 1975;Kimura et al, 1964;Kimura and Wersall, 1962;Nadol, 1981Nadol, , 1983aOmata and Schatzle, 1980;Osborne, 1977;Rodriguez-Echandia, 1967;Smith, 1967;Sobkowicz et al, 1982Sobkowicz et al, , 1986Spoendlin, 1966Spoendlin, , 1969Wersall et al, 1961).…”

Section: Introductionmentioning

confidence: 99%

Freeze‐fracture organization of hair cell synapses in the sensory epithelium of guinea pig organ of Corti

Saito

1990

J. Elec. Microsc. Tech.

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The fine structure of both the afferent and efferent hair cell synapses in the sensory epithelium of guinea pig organ of Corti was examined by freeze-fracture electron microscopy. In the afferent synapse, barlike aggregates of intramembrane particles (IMPs) of about 10 nm in diameter were seen on the P-face of the afferent presynaptic membrane directly beneath the presynaptic dense projection which is located in the active zone of the presynaptic membrane. Small and large depressions have been seen on the presynaptic membrane. The former were observed in the proximity of the barlike aggregates, while the latter were observed some distance from the aggregate. In outer hair cells, IMPs of about 10 nm in diameter were seen on the P-face of the afferent postsynaptic membrane at a density of 3,000/microns 2. In the efferent synapse, many aggregates composed of from several to tens of large IMPs of 13 nm in diameter were observed on the presynaptic membrane. These aggregates were localized to small membrane depressions, which tended to be deeper as particle number per aggregate increased. Dense populations of IMPs of about 9 nm in diameter were observed on the P-face of the efferent postsynaptic membrane at a density of 4,000/microns 2. A fenestrated subsynaptic cistern completely covers the efferent postsynaptic membrane. Moreover, the subsynaptic cistern spans several efferent postsynaptic membranes when efferent synapses are gathered in a group. In the afferent and efferent synapses of hair cells, specializations of the synaptic membranes were represented by marked aggregates characteristic of IMPs. In the efferent synapse, IMP movement inside the synaptic membrane was proposed in relationship to retrival of synaptic vesicle membrane. Structural relationship between the subsynaptic cistern and efferent postsynaptic membrane was revealed.

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Afferent and efferent nerve endings of the outer hair cells in the rahbit

Cited by 10 publications

References 4 publications

Quantitative analysis of multivesicular bodies (MVBs) in the hypoglossal nerve: Evidence that neurotrophic factors do not use MVBs for retrograde axonal transport

Quantitative analysis of multivesicular bodies (MVBs) in the hypoglossal nerve: Evidence that neurotrophic factors do not use MVBs for retrograde axonal transport

Multivesicular bodies in neurons: Distribution, protein content, and trafficking functions

Freeze‐fracture organization of hair cell synapses in the sensory epithelium of guinea pig organ of Corti

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