scholarly journals Generation of New Neurons in Dorsal Root Ganglia in Adult Rats after Peripheral Nerve Crush Injury

2015 ◽  
Vol 2015 ◽  
pp. 1-12 ◽  
Author(s):  
Luisa Muratori ◽  
Giulia Ronchi ◽  
Stefania Raimondo ◽  
Stefano Geuna ◽  
Maria Giuseppina Giacobini-Robecchi ◽  
...  
Keyword(s):  
Sensory Neurons ◽  
Dorsal Root Ganglia ◽  
Dorsal Root ◽  
Morphological Changes ◽  
Dorsal Root Ganglion Neurons ◽  
Cell Phenotype ◽  
Adult Rats ◽  
Nerve Crush ◽  
Satellite Glial Cells ◽  
Ganglion Neurons

The evidence of neurons generatedex novoin sensory ganglia of adult animals is still debated. In the present study, we investigated, using high resolution light microscopy and stereological analysis, the changes in the number of neurons in dorsal root ganglia after 30 days from a crush lesion of the rat brachial plexus terminal branches. Results showed, as expected, a relevant hypertrophy of dorsal root ganglion neurons. In addition, we reported, for the first time in the literature, that neuronal hypertrophy was accompanied by massive neuronal hyperplasia leading to a 42% increase of the number of primary sensory neurons. Moreover, ultrastructural analyses on sensory neurons showed that there was not a relevant neuronal loss as a consequence of the nerve injury. The evidence of BrdU-immunopositive neurons and neural progenitors labeled with Ki67, nanog, nestin, and sox-2 confirmed the stereological evidence of posttraumatic neurogenesis in dorsal root ganglia. Analysis of morphological changes following axonal damage in addition to immunofluorescence characterization of cell phenotype suggested that the neuronal precursors which give rise to the newly generated neurons could be represented by satellite glial cells that actively proliferate after the lesion and are able to differentiate toward the neuronal lineage.

scholarly journals CHANGES IN THE DISTRIBUTION OF A HISTONE IN DORSAL ROOT GANGLION NEURONS DURING DEVELOPMENT

1968 ◽  
Vol 38 (3) ◽  
pp. 515-522 ◽  
Author(s):  
Steven E. Kornguth ◽  
Lawrence G. Tomasi
Keyword(s):  
Dorsal Root Ganglia ◽  
Dorsal Root ◽  
Nervous Tissue ◽  
Cellular Localization ◽  
Basic Protein ◽  
Cell Function ◽  
Dorsal Root Ganglion Neurons ◽  
Adult Rats ◽  
Tissue Specific ◽  
Ganglion Neurons

The isolation and cellular localization of a basic protein (histone) from central nervous tissue have been previously reported. In the tissues previously studied (nervous tissue, testis, liver, spleen, kidney, ovary), the basic protein was restricted in distribution to the nuclei of neurons and spermatogonia. In the present study, the temporal appearance of the histone within neurons and the changes in its distribution during ontogenesis were examined. The reaction between a fluorescent immune γ-globulin prepared against this purified tissue-specific histone and the neurons from the dorsal root ganglia of the rat was investigated. The dorsal root ganglia examined were those from fetuses, 2-, 10-, and 40-day-old rats, and from adult rats. At the earliest stages, only the nucleoli reacted. Subsequently, threads of fluorescent material were seen to emerge from the nucleoli. The extent of this reaction between the immune globulin and the threads within the nuclei continued to increase with maturation. No changes in fluorescence localization during development could be seen in the nuclei of neurons in the cerebellum or brain stem. The role that this tissue-specific histone may play in cell function is discussed.

Delta/Notch signaling promotes formation of zebrafish neural crest by repressing Neurogenin 1 function

Development ◽  
2002 ◽  
Vol 129 (11) ◽  
pp. 2639-2648 ◽  
Author(s):  
Robert A. Cornell ◽  
Judith S. Eisen
Keyword(s):  
Dorsal Root Ganglion ◽  
Neural Crest ◽  
Notch Signaling ◽  
Sensory Neurons ◽  
Dorsal Root ◽  
Cell Formation ◽  
Dorsal Root Ganglion Neurons ◽  
Primary Neurons ◽  
Different Types ◽  
Ganglion Neurons

In zebrafish, cells at the lateral edge of the neural plate become Rohon-Beard primary sensory neurons or neural crest. Delta/Notch signaling is required for neural crest formation. ngn1 is expressed in primary neurons; inhibiting Ngn1 activity prevents Rohon-Beard cell formation but not formation of other primary neurons. Reducing Ngn1 activity in embryos lacking Delta/Notch signaling restores neural crest formation, indicating Delta/Notch signaling inhibits neurogenesis without actively promoting neural crest. Ngn1 activity is also required for later development of dorsal root ganglion sensory neurons; however, Rohon-Beard neurons and dorsal root ganglion neurons are not necessarily derived from the same precursor cell. We propose that temporally distinct episodes of Ngn1 activity in the same precursor population specify these two different types of sensory neurons.

Interaction of opioids and membrane potential to modulate Ca2+ channels in rat dorsal root ganglion neurons

1995 ◽  
Vol 73 (5) ◽  
pp. 1793-1798 ◽  
Author(s):  
M. D. Womack ◽  
E. W. McCleskey
Keyword(s):  
Dorsal Root Ganglion ◽  
Sensory Neurons ◽  
Action Potentials ◽  
Dorsal Root ◽  
Dorsal Root Ganglion Neurons ◽  
High Threshold ◽  
Partial Recovery ◽  
Drg Neurons ◽  
Ganglion Neurons ◽  
Ca2 Channels

1. Using patch-clamp methods, we show that brief prepulses to very positive voltages increase (facilitate) the amplitude of current through Ca2+ channels during a subsequent test pulse in some, but not all, dorsal root ganglion (DRG) sensory neurons. The amplitude of this facilitated current generally increases when the Ca2+ channels are inhibited by activation of the mu-opioid receptor. 2. The facilitated current is blocked by omega-conotoxin GVIA, activates in the range of high-threshold Ca2+ channels, and inactivates at relatively negative holding voltages. Thus facilitated current passes through N-type Ca2+ channels, the same channels that are inhibited by opioids and control neurotransmitter release in sensory neurons. 3. Although maximal facilitation occurs only at unphysiologically high membrane potentials (above +100 mV), some facilitation is seen after prepulses to voltages reached during action potentials. After return to the holding potential, facilitation persists for hundreds of milliseconds, considerably longer than in other neurons. Brief trains of pulses designed to mimic action potentials caused small facilitation (19% of maximal) in a fraction (8 of 24) of opioid-inhibited neurons. 4. We conclude that 1) prepulses to extremely positive voltages can cause partial recovery of Ca2+ channels inhibited by opioids; and 2) small, but detectable, facilitation is also seen after physiological stimulation in some DRG neurons. Facilitation, largely considered a biophysical epiphenomenon because of the extreme voltages used to induce it, appears to be physiologically relevant during opioid inhibition of Ca2+ channels in DRG neurons.

6. Dorsal root ganglion neurons: electrical properties and cell type

1985 ◽  
Vol 308 (1136) ◽  
pp. 412-413
Keyword(s):  
Electrical Properties ◽  
Dorsal Root Ganglion ◽  
Dorsal Root Ganglia ◽  
Dorsal Root ◽  
Dorsal Root Ganglion Neurons ◽  
Cell Type ◽  
Neuronal Types ◽  
Ganglion Neurons ◽  
Two Populations ◽  
Normally Distributed

It has been shown that there are two main morphological neuronal types in rat and mouse dorsal root ganglia (d.r.g.s), the large light (LL) and small dark (s.d.) neurons. Each population has a normally distributed range of cell sizes with different means, and the size ranges of the two populations overlap (Lawson 1979; Lawson & Harper, in press).

scholarly journals Activity and Ca2+ regulate the mobility of TRPV1 channels in the plasma membrane of sensory neurons

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Eric N Senning ◽  
Sharona E Gordon
Keyword(s):  
Plasma Membrane ◽  
Sensory Neurons ◽  
Dorsal Root ◽  
Optical Recording ◽  
Dorsal Root Ganglion Neurons ◽  
Mechanical Stimuli ◽  
Channel Activation ◽  
Trpv1 Channels ◽  
Ganglion Neurons ◽  
Ca2 Channels

TRPV1 channels are gated by a variety of thermal, chemical, and mechanical stimuli. We used optical recording of Ca2+ influx through TRPV1 to measure activity and mobility of single TRPV1 molecules in isolated dorsal root ganglion neurons and cell lines. The opening of single TRPV1 channels produced sparklets, representing localized regions of elevated Ca2+. Unlike sparklets reported for L-type Ca2+ channels, TRPV4 channels, and AchR channels, TRPV1 channels diffused laterally in the plasma membrane as they gated. Mobility was highly variable from channel-to-channel and, to a smaller extent, from cell to cell. Most surprisingly, we found that mobility decreased upon channel activation by capsaicin, but only in the presence of extracellular Ca2+. We propose that decreased mobility of open TRPV1 could act as a diffusion trap to concentrate channels in cell regions with high activity.

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