scholarly journals Regional Differences of Serotonin-Mediated Synaptic Plasticity in the Chicken Spinal Cord With Development and Aging

1997 ◽  
Vol 6 (1) ◽  
pp. 41-48 ◽  
Author(s):  
Ling Chen ◽  
Kayoko Hamaguchi ◽  
Shun Hamada ◽  
Nobuo Okado
Keyword(s):  
Spinal Cord ◽  
Synaptic Plasticity ◽  
Dorsal Horn ◽  
Synapse Formation ◽  
Ventral Horn ◽  
Lamina I ◽  
Age Related ◽  
Dorsal Horns ◽  
Development And Aging ◽  
Axodendritic Synapses

Previous studies in our laboratory /3,17/ have demonstrated that serotonin (5-HT) appears to have a trophic-like effect in enhancing synapse formation and maintenance in both the developing and the adult central nervous system. In the present study, we focused on age-related changes in the density of the axosomatic and axodendritic synapses and the number of 5-HT-positive fibers in the chicken spinal cord, with special reference to differences between the ventral (laminae VII and IX) and the dorsal (lamina I) horn. At 1 week posthatching (PIW), a transient overproduction of synapses and 5-HT-immunoreactive fibers occurred in lamina IX; all parameters had returned to their initial levels by 1 month post-hatching (PIM). The density of synapses further decreased by about 40% between P6M and P2Y (2 years posthatching). Although the magnitude of the transient increase in lamina VII was less than that in lamina IX, the changing pattern of the synapses and the 5-HT-positive fibers was similar in both regions. In the ventral horn, thin 5-HT-positive fibers were most prominent at P1W and then decreased with development; thin 5-HT-positive fibers were still found at P6M but had almost disappeared by P2Y. By contrast, at P2Y the density of the synapses and the 5-HT-positive fibers in the dorsal horn was even higher than that of younger animals.Reduction of 5-HT levels in P2Y-old chickens by p-chlorophenylalanine (pCPA) administration decreased the synaptic density in lamina I but not in lamina IX. The results of this study demonstrate that 5-HT-mediated synaptic plasticity is markedly different in the ventral and dorsal horns of the aged chicken. In the ventral horn, synaptic plasticity reached a maximum at about P1W, remained stable in the young-adult period, and then finally disappeared in the aged chicken. Conversely, the results suggest that in the dorsal horn, 5-HT fibers continue to mediate the trophic influence on synaptic plasticity even in the old chicken.

Distribution of substance P in the spinal cord of patients with syringomyelia

1996 ◽  
Vol 84 (6) ◽  
pp. 992-998 ◽  
Author(s):  
Thomas H. Milhorat ◽  
Harrison T. M. Mu ◽  
Carole C. LaMotte ◽  
Ade T. Milhorat
Keyword(s):  
Spinal Cord ◽  
Substance P ◽  
Dorsal Horn ◽  
Ventral Horn ◽  
Immunohistochemical Method ◽  
Positive Staining ◽  
Content Type ◽  
Normal Individuals ◽  
Neurologically Normal ◽  
Intermediolateral Nucleus

✓ The distribution of substance P, a putative neurotransmitter and pain-related peptide, was studied using the peroxidase—antiperoxidase immunohistochemical method in the spinal cords obtained from autopsy of 10 patients with syringomyelia and 10 age- and sex-matched, neurologically normal individuals. Substance P immunoreactivity was present in axons and in terminal-like processes in close apposition to neurons in the first, second, and third laminae of the dorsal horn. Smaller amounts of peroxidase-positive staining were found in the fifth lamina of the dorsal horn, the intermediolateral nucleus, the intermediomedial nucleus, and the ventral horn. In nine of 10 patients with syringomyelia, there was a substantial increase in substance P immunoreactivity in the first, second, third, and fifth laminae below the level of the lesion. A marked reduction or absence of staining was present in segments of the spinal cord occupied by the syrinx. Central cavities produced bilateral abnormalities, whereas eccentric cavities produced changes that were ipsilateral to the lesion. No alterations in staining were found in the spinal cord of an asymptomatic patient with a small central syrinx. The authors conclude that syringomyelia can be associated with abnormalities in spinal cord levels of substance P, which may affect the modulation and perception of pain.

Plasticity to neonatal sensorimotor cortex injury

2010 ◽  
Vol 1 (1) ◽  
Author(s):  
Sarah Galley ◽  
Gavin Clowry
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Sensorimotor Cortex ◽  
Corticospinal Tract ◽  
Fluorescent Protein ◽  
Yellow Fluorescent Protein ◽  
Red Nucleus ◽  
Neuronal Cell ◽  
Ventral Horn ◽  
Dorsal Funiculus

AbstractA CST-YFP transgenic mouse has been developed for the study of the corticospinal tract in which yellow fluorescent protein is expressed under the control of thy1 and emx1 promoters in order to restrict expression to forebrain neurones. We explored plasticity of the developing corticospinal tract of these mice following a unilateral lesion to the sensorimotor cortex at postnatal day 7. The extent of innervation of the cervical spinal cord at time points post-lesion was assessed by measuring density of immunoperoxidase reactivity for yellow fluorescent protein in the dorsal funiculi and a defined region of each dorsal horn, and by counting immunoreactive axonal varicosities in the ventral horns. Two/three days post-lesion, the density of immunoreactivity in the dorsal horn contralateral to the lesion was reduced proportional to the decrease in positive fibres in the dorsal funiculus, however density of immunoreactive varicosities in the ventral horn was more resistant to loss. Over a three week period, immunoreactive axonal processes in the grey matter increased on the contralateral side, particularly in the ventral horn, but without an increase in immunopositive fibres in the contralateral dorsal funiculus, demonstrating sprouting of surviving immunoreactive fibres to replace lesioned corticospinal axons. However, the origin of sprouting fibres could not be identified with confidence as parallel observations revealed strongly immunoreactive neuronal cell bodies in the spinal cord, medulla and red nucleus. We have demonstrated plasticity in response to a developmental lesion but discovered a drawback to using these mice if visualisation of individual axons is enhanced by immunohistochemistry.

scholarly journals Differential astroglial responses in the spinal cord of rats submitted to a sciatic nerve double crush treated with local injection of cultured Schwann cell suspension or lesioned spinal cord extract: implications on cell therapy for nerve repair

2007 ◽  
Vol 22 (6) ◽  
pp. 485-494 ◽  
Author(s):  
João Gabriel Martins Dallo ◽  
Bernardo Vergara Reichert ◽  
José Benedito Ramos Valladão Júnior ◽  
Camila Silva ◽  
Bianca Aparecida de Luca ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Sciatic Nerve ◽  
Cell Therapy ◽  
Dorsal Horn ◽  
Wound Repair ◽  
Ventral Horn ◽  
Local Injection ◽  
Spinal Cord Dorsal Horn ◽  
Nerve Lesion ◽  
Double Crush

PURPOSE: Reactive astrocytes are implicated in several mechanisms after central or peripheral nervous system lesion, including neuroprotection, neuronal sprouting, neurotransmission and neuropathic pain. Schwann cells (SC), a peripheral glia, also react after nerve lesion favoring wound/repair, fiber outgrowth and neuronal regeneration. We investigated herein whether cell therapy for repair of lesioned sciatic nerve may change the pattern of astroglial activation in the spinal cord ventral or dorsal horn of the rat. METHODS: Injections of a cultured SC suspension or a lesioned spinal cord homogenized extract were made in a reservoir promoted by a contiguous double crush of the rat sciatic nerve. Local injection of phosphate buffered saline (PBS) served as control. One week later, rats were euthanized and spinal cord astrocytes were labeled by immunohistochemistry and quantified by means of quantitative image analysis. RESULTS: In the ipsilateral ventral horn, slight astroglial activations were seen after PBS or SC injections, however, a substantial activation was achieved after cord extract injection in the sciatic nerve reservoir. Moreover, SC suspension and cord extract injections were able to promote astroglial reaction in the spinal cord dorsal horn bilaterally. Conclusion: Spinal cord astrocytes react according to repair processes of axotomized nerve, which may influence the functional outcome. The event should be considered during the neurosurgery strategies.

Visualization of lamina I of the dorsal horn in live adult rat spinal cord slices

2000 ◽  
Vol 96 (2) ◽  
pp. 133-142 ◽  
Author(s):  
Nadège Chéry ◽  
Xiao Hong Yu ◽  
Yves De Koninck
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Rat Spinal Cord ◽  
Adult Rat ◽  
Lamina I ◽  
Adult Rat Spinal Cord

scholarly journals Age-related gene expression changes in lumbar spinal cord: Implications for neuropathic pain

2020 ◽  
Vol 16 ◽  
pp. 174480692097191
Author(s):  
Jack A Mayhew ◽  
Mitchell J Cummins ◽  
Ethan T Cresswell ◽  
Robert J Callister ◽  
Doug W Smith ◽  
...  
Keyword(s):  
Gene Expression ◽  
Spinal Cord ◽  
Neuropathic Pain ◽  
Dorsal Horn ◽  
Dorsal Spinal Cord ◽  
Age Related ◽  
Pathological Pain ◽  
The Impact ◽  
Dorsal Spinal ◽  
Young Mice

Clinically, pain has an uneven incidence throughout lifespan and impacts more on the elderly. In contrast, preclinical models of pathological pain have typically used juvenile or young adult animals to highlight the involvement of glial populations, proinflammatory cytokines, and chemokines in the onset and maintenance of pathological signalling in the spinal dorsal horn. The potential impact of this mismatch is also complicated by the growing appreciation that the aged central nervous system exists in a state of chronic inflammation because of enhanced proinflammatory cytokine/chemokine signalling and glial activation. To address this issue, we investigated the impact of aging on the expression of genes that have been associated with neuropathic pain, glial signalling, neurotransmission and neuroinflammation. We used qRT-PCR to quantify gene expression and focussed on the dorsal horn of the spinal cord as this is an important perturbation site in neuropathic pain. To control for global vs region-specific age-related changes in gene expression, the ventral half of the spinal cord was examined. Our results show that expression of proinflammatory chemokines, pattern recognition receptors, and neurotransmitter system components was significantly altered in aged (24–32 months) versus young mice (2–4 months). Notably, the magnitude and direction of these changes were spinal-cord region dependent. For example, expression of the chemokine, Cxcl13, increased 119-fold in dorsal spinal cord, but only 2-fold in the ventral spinal cord of old versus young mice. Therefore, we propose the dorsal spinal cord of old animals is subject to region-specific alterations that prime circuits for the development of pathological pain, potentially in the absence of the peripheral triggers normally associated with these conditions.

Localization of Spinal Neurons Activated During Locomotion Using the c-fos Immunohistochemical Method

2005 ◽  
Vol 93 (6) ◽  
pp. 3442-3452 ◽  
Author(s):  
X. Dai ◽  
B. R. Noga ◽  
J. R. Douglas ◽  
L. M. Jordan
Keyword(s):  
Spinal Cord ◽  
Dorsal Horn ◽  
Blocking Agent ◽  
Neuromuscular Blocking ◽  
Ventral Horn ◽  
Afferent Feedback ◽  
Immunohistochemical Method ◽  
Fictive Locomotion ◽  
Adult Cat ◽  
Treadmill Locomotion

The c-fos immunohistochemical method of activity-dependent labeling was used to localize locomotor-activated neurons in the adult cat spinal cord. In decerebrate cats, treadmill locomotion was evoked by electrical stimulation of the mesencephalic locomotor region (MLR). Spontaneous or MLR-evoked fictive locomotion was produced in decerebrate animals paralyzed with a neuromuscular blocking agent. After bouts of locomotion during a 7- to 9-h time period, the animals were perfused and the L3–S1 spinal cord segments removed for immunohistochemistry. Control animals were subjected to the same surgical procedures but no locomotor task. Labeled cells were concentrated in Rexed's laminae III and IV of the dorsal horn and laminae VII, VIII, and X of the intermediate zone/ventral horn after treadmill locomotion. Cells in laminae VII, VIII, and X were labeled after fictive locomotion, but labeling in the dorsal horn was much reduced. In control animals, c- fos labeling was a small fraction of that observed in the locomotor animals. The results suggest that labeled cells in laminae VII, VIII, and X are premotor interneurons involved in the production of locomotion, whereas the laminae III and IV cells are those activated during locomotion due to afferent feedback from the moving limb. c-fos-labeled cells were most numerous in the L5–L7 segments, consistent with the distribution of locomotor activated neurons detected through the use of MLR-evoked field potentials.

scholarly journals Glycine-specific synapses in rat spinal cord. Identification by electron microscope autoradiography.

1976 ◽  
Vol 68 (2) ◽  
pp. 389-395 ◽  
Author(s):  
D L Price ◽  
A Stocks ◽  
J W Griffin ◽  
A Young ◽  
K Peck
Keyword(s):  
Spinal Cord ◽  
Electron Microscope ◽  
Motor Neurons ◽  
Ventral Horn ◽  
Uptake System ◽  
Electron Microscope Autoradiography ◽  
Spinal Motor Neurons ◽  
Microscope Autoradiography ◽  
Axodendritic Synapses

Glycine, an inhibitory transmitter in spinal cord, is taken up into specific nerve terminals by means of a unique high-affinity uptake system. In this study, [3H]glycine was directly microinjected into rat ventral horn in vivo and electron microscope autoradiography used to localize the label in various anatomic compartments. Quantiative analysis showed that [3H]glycine labeled a high proportion of axosomatic and axodendritic synapses which presumably act to inhibit spinal motor neurons.

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