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Paola Paggi - One of the best experts on this subject based on the ideXlab platform.

  • nicotinic acetylcholine receptor subtypes in the rat sympathetic ganglion pharmacological characterization subcellular distribution and effect of pre and Postganglionic Nerve crush
    Journal of Neuropathology and Experimental Neurology, 2004
    Co-Authors: Arianna Del Signore, M. Moretti, C. Gotti, Angela Rizzo, Paola Paggi
    Abstract:

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and Postganglionic Nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the alpha3 subunit associated with beta4 and/or beta2 subunits that bind 3H-Epibatidine with high affinity, and those containing the alpha7 subunit that bind 125I-alphaBungarotoxin. After Postganglionic Nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating Postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic Nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG.

  • differential regulation of transcripts for dystrophin isoforms dystroglycan and α3achr subunit in mouse sympathetic ganglia following Postganglionic Nerve crush
    Neurobiology of Disease, 2001
    Co-Authors: M L Zaccaria, Tamara C Petrucci, C Perronecapano, G Meluccivigo, L Gaeta, Paola Paggi
    Abstract:

    Previous data suggest that in mouse superior cervical ganglion (SCG) the dystrophin-dystroglycan complex may be involved in the axotomy-induced intraganglionic synapse remodeling. Here we analyzed the levels of mRNAs encoding dystrophins, dystroglycan (Dg), and the alpha3 subunit of the nicotinic acetylcholine receptor (alpha3AChR) in mouse SCG at various postaxotomy intervals. We found that axotomy downregulates the levels of transcripts for molecules related to synaptic transmission (alpha3AChR) and those presumably involved in postsynaptic apparatus organization (dystrophin isoforms) and upregulates the transcript encoding Dg, which, by binding dystrophin, bridges the actin cytoskeleton and several extracellular matrix proteins and may thus be involved in postaxotomy neuronal recovery. The observed transcriptional modulation of the components of dystrophin-dystroglycan complexes indicates their involvement in injury-induced neuronal plasticity and suggests a role in other forms of plasticity such as those required in learning and memory, functions often impaired in Duchenne muscular dystrophy patients.

  • selective reduction in the nicotinic acetylcholine receptor and dystroglycan at the postsynaptic apparatus of mdx mouse superior cervical ganglion
    Journal of Neuropathology and Experimental Neurology, 2000
    Co-Authors: Letizia M Zaccaria, C. Gotti, Egle M De Stefano, Tamara C Petrucci, Paola Paggi
    Abstract:

    Our previous data suggested that in mouse sympathetic superior cervical ganglion (SCG) the dystrophin-dystro- glycan complex may be involved in the stabilization of the nicotinic acetylcholine receptor (nAChR) clusters. Here we used SCG of dystrophic mdx mice, which express only the shorter isoforms of dystrophin (Dys), to investigate whether the lack of the full-length dystrophin (Dp427) could affect the localization of the dystroglycan and the a3 nAChR subunit (a3AChR) at the postsynaptic apparatus. We found a selective reduction in intraganglionic postsynaptic specializations immunopositive for a3AChR and for a- and b-dystroglycan compared with the wild-type. Moreover, in mdx mice, unlike the wild-type, the disassembly of intraganglionic synapses induced by Postganglionic Nerve crush occurred at the slower rate and was not preceded by the loss of immunoreactivity for Dys isoforms, b-dystroglycan, and a3AChR. These data indicate that the absence of Dp427 at the intraganglionic postsynaptic apparatus of mdx mouse SCG interferes with the presence of both dystroglycan and nAChR clusters at these sites and affects the rate of synapse disassembly induced by Postganglionic Nerve crush. Moreover, they suggest that the decrease in ganglionic nAChR may be one of the factors responsible for autonomic imbalance described in Duchenne muscular dystrophy patients.

  • Ultrastructural alterations induced in quail ciliary neurons by Postganglionic Nerve crush and by Ricinus toxin administration, separately and in combination.
    Neuroscience, 1994
    Co-Authors: M. E. De Stefano, A. Ciofi Luzzatto, Enrico Mugnaini, Paola Paggi, Giovanni Toschi
    Abstract:

    Abstract The response to Postganglionic Nerve crush and Ricinus toxin administration by the ciliary neurons of the quail ciliary ganglion was investigated at the ultrastructural level. The toxin was either applied at the crush site on the Postganglionic Nerves or injected into the anterior eye chamber without any other operative intervention. Crush of Postganglionic Nerves without toxin administration and saline injection into the anterior eye chamber served as controls for the two toxin administration procedures. Postganglionic Nerve crush caused a distinct chromatolytic reaction, accompanied by massive detachment of the preganglionic axon terminals from the ciliary neurons and loss of most of the synapses, both chemical and electrical. This process does not induce cell death and is reversible. Saline injection in the anterior eye chamber caused a moderate retrograde reaction in some of the ciliary neurons, presumably as a consequence of paracentesis. The changes consisted mainly of an increase of perikaryal neurofilaments with, at most, a minor detachment of the preganglionic boutons from a small portion of the cell body at the nuclear pole. Ricinus toxin administration induced neuronal degeneration following a pattern common to both delivery modes. The degenerative process consisted of disruption and detachment of polyribosomes from the rough endoplasmic reticulum, an increase of smooth cisterns and tubules, a dramatic increase of neurofilament bundles, compartmentalization of the cytoplasmic organelles and, finally, karyorrhexis and cell lysis. The final stages of Ricinus toxin degeneration involve a progressive accumulation of extracellular flocculo-filamentous material and cell lysis. After administration of Ricinus toxin to the crush site, ricin-affected neurons showed withdrawal of the preganglionic boutons from a portion of the ciliary neuron, especially at the nuclear pole. After Ricinus toxin injection into the anterior eye chamber, however, the bouton shell surrounding the affected ciliary neurons remained intact in the early stages of degeneration. Detachment of the preganglionic terminals and disruption of the cell junctions, therefore, is the consequence of Nerve crush and not of the toxin itself. This study demonstrates that quail ciliary neurons are a suitable model for experimental neuropathology and neurotoxicology.

C. Gotti - One of the best experts on this subject based on the ideXlab platform.

  • nicotinic acetylcholine receptor subtypes in the rat sympathetic ganglion pharmacological characterization subcellular distribution and effect of pre and Postganglionic Nerve crush
    Journal of Neuropathology and Experimental Neurology, 2004
    Co-Authors: Arianna Del Signore, M. Moretti, C. Gotti, Angela Rizzo, Paola Paggi
    Abstract:

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and Postganglionic Nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the alpha3 subunit associated with beta4 and/or beta2 subunits that bind 3H-Epibatidine with high affinity, and those containing the alpha7 subunit that bind 125I-alphaBungarotoxin. After Postganglionic Nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating Postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic Nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG.

  • Nicotinic Acetylcholine Receptor Subtypes in the Rat Sympathetic Ganglion: Pharmacological Characterization, Subcellular Distribution and Effect of Pre- and Postganglionic Nerve Crush
    American Association of Neuropathologists:University of Iowa College of Medicine Division of Neuropathology Rm. 148A-ML:Iowa City IA 52242:(319)335-82, 2004
    Co-Authors: Del Signore Arianna, C. Gotti, Rizzo Angela, M. Moretti, Paggi Paola
    Abstract:

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and Postganglionic Nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the α3 subunit associated with β4 and/or β2 subunits that bind 3H-Epibatidine with high affinity, and those containing the α7 subunit that bind 125I-αBungarotoxin. After Postganglionic Nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating Postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic Nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG

  • selective reduction in the nicotinic acetylcholine receptor and dystroglycan at the postsynaptic apparatus of mdx mouse superior cervical ganglion
    Journal of Neuropathology and Experimental Neurology, 2000
    Co-Authors: Letizia M Zaccaria, C. Gotti, Egle M De Stefano, Tamara C Petrucci, Paola Paggi
    Abstract:

    Our previous data suggested that in mouse sympathetic superior cervical ganglion (SCG) the dystrophin-dystro- glycan complex may be involved in the stabilization of the nicotinic acetylcholine receptor (nAChR) clusters. Here we used SCG of dystrophic mdx mice, which express only the shorter isoforms of dystrophin (Dys), to investigate whether the lack of the full-length dystrophin (Dp427) could affect the localization of the dystroglycan and the a3 nAChR subunit (a3AChR) at the postsynaptic apparatus. We found a selective reduction in intraganglionic postsynaptic specializations immunopositive for a3AChR and for a- and b-dystroglycan compared with the wild-type. Moreover, in mdx mice, unlike the wild-type, the disassembly of intraganglionic synapses induced by Postganglionic Nerve crush occurred at the slower rate and was not preceded by the loss of immunoreactivity for Dys isoforms, b-dystroglycan, and a3AChR. These data indicate that the absence of Dp427 at the intraganglionic postsynaptic apparatus of mdx mouse SCG interferes with the presence of both dystroglycan and nAChR clusters at these sites and affects the rate of synapse disassembly induced by Postganglionic Nerve crush. Moreover, they suggest that the decrease in ganglionic nAChR may be one of the factors responsible for autonomic imbalance described in Duchenne muscular dystrophy patients.

Arianna Del Signore - One of the best experts on this subject based on the ideXlab platform.

  • nicotinic acetylcholine receptor subtypes in the rat sympathetic ganglion pharmacological characterization subcellular distribution and effect of pre and Postganglionic Nerve crush
    Journal of Neuropathology and Experimental Neurology, 2004
    Co-Authors: Arianna Del Signore, M. Moretti, C. Gotti, Angela Rizzo, Paola Paggi
    Abstract:

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and Postganglionic Nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the alpha3 subunit associated with beta4 and/or beta2 subunits that bind 3H-Epibatidine with high affinity, and those containing the alpha7 subunit that bind 125I-alphaBungarotoxin. After Postganglionic Nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating Postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic Nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG.

Yasuyuki Kitada - One of the best experts on this subject based on the ideXlab platform.

  • Parasympathetic Postganglionic Nerve Fibers in the Fungiform Papillae of the Frog
    Olfaction and Taste XI, 1994
    Co-Authors: Katsuhiro Inoue, Yasuyuki Kitada
    Abstract:

    The Nerve bundle in each fungiform papilla of the frog consists of afferent, and sympathetic and parasympathetic efferent Nerve fibers. Efferent control of the gustatory system has been postulated from electronphysiological evidence, but there is inadequate morphological evidence for such a conclusion. Some unmyelinated Nerve fibers in the Nerve bundle of each fungiform papilla originate from parasympathetic Postganglionic neurons within the lingual branch of the glossopharyngeal Nerve [1,2]. Particular Nerve endings, designated parasympathetic efferent according to morphological criteria, namely, the presence of accumulations of clear synaptic vesicles and mitochondria, besides a specific membrane system, at the regions of contact between the Nerve endings and taste cells, have been observed in the taste organs of mammals, fish, and frogs. However, the presence of sensory Nerve endings that contained many typical, clear synaptic vesicles of the type usually associated with cholinergic fibers has also been reported.

  • parasympathetic Postganglionic Nerve fibers in the fungiform papillae of the bullfrog rana catesbeiana
    Brain Research, 1992
    Co-Authors: Katsuhiro Inoue, T Yamaai, Yasuyuki Kitada
    Abstract:

    An investigation was made of the precise origin of the unmyelinated Nerve fibers in the fungiform papillae of the bullfrog's tongue. Some unmyelinated Nerve fibers in the fungiform papillae originate from the parasympathetic Postganglionic cells in the glossopharyngeal Nerve. Axonal enlargements of the parasympathetic Nerve fibers were in close contact with the Merkel-like basal or supporting cells in the taste disk. These results seem to provide morphological evidence for the existence of an efferent control system in the taste disk.

M. Moretti - One of the best experts on this subject based on the ideXlab platform.

  • nicotinic acetylcholine receptor subtypes in the rat sympathetic ganglion pharmacological characterization subcellular distribution and effect of pre and Postganglionic Nerve crush
    Journal of Neuropathology and Experimental Neurology, 2004
    Co-Authors: Arianna Del Signore, M. Moretti, C. Gotti, Angela Rizzo, Paola Paggi
    Abstract:

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and Postganglionic Nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the alpha3 subunit associated with beta4 and/or beta2 subunits that bind 3H-Epibatidine with high affinity, and those containing the alpha7 subunit that bind 125I-alphaBungarotoxin. After Postganglionic Nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating Postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic Nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG.

  • Nicotinic Acetylcholine Receptor Subtypes in the Rat Sympathetic Ganglion: Pharmacological Characterization, Subcellular Distribution and Effect of Pre- and Postganglionic Nerve Crush
    American Association of Neuropathologists:University of Iowa College of Medicine Division of Neuropathology Rm. 148A-ML:Iowa City IA 52242:(319)335-82, 2004
    Co-Authors: Del Signore Arianna, C. Gotti, Rizzo Angela, M. Moretti, Paggi Paola
    Abstract:

    Nicotinic acetylcholine receptors (nAChRs) mediate fast synaptic transmission in autonomic ganglia, which innervate and control the activity of most visceral organs. By combining ultrastructural, immunocytochemical, and pharmacological analyses, we characterized the nAChR subtypes in the rat superior cervical ganglion (SCG) and the effect of pre- and Postganglionic Nerve crush on their number in the ganglion and their distribution at the intraganglionic synapses. Binding with radioactive nicotinic ligands, immunoprecipitation, and immunolocalization experiments revealed the presence of different nAChR subtypes: those containing the α3 subunit associated with β4 and/or β2 subunits that bind 3H-Epibatidine with high affinity, and those containing the α7 subunit that bind 125I-αBungarotoxin. After Postganglionic Nerve crush, the number of nicotinic receptors and immunopositive intraganglionic synapses for each nAChR subunit strongly decreased. Both the number of nAChRs and immunoreactivity recovered 26 days after injury, when regenerating Postganglionic fibers had reinnervated the peripheral target organs, as shown by the restoration of tyrosine hydroxylase immunoreactivity in the iris. This observation and the lack of any effect of preganglionic Nerve crush on the number of nicotinic receptors suggest that the peripheral targets affect the organization of intraganglionic synapses in adult SCG