Processing of Sensory Information in the Superficial Dorsal Horn of the Spinal Cord

This book constitutes the proceedings of a NATO Advanced Research Workshop held in El Escorial (Spain) from 22 -27 May 1988 with the title Processing of sensory information in the superficial dorsal hom of the spinal cord.

Author: F. Cervero

Publisher: Springer Science & Business Media

ISBN: 9781461308256

Category: Science

Page: 530

View: 940

DOWNLOAD →

This book constitutes the proceedings of a NATO Advanced Research Workshop held in El Escorial (Spain) from 22 -27 May 1988 with the title Processing of sensory information in the superficial dorsal hom of the spinal cord. Included in the book are reports of most of the main lectures given at the meeting, section introductions written by each session Chairman, section reports compiled by session rapporteurs and some short papers invited from authors of communications given in poster form. The latter were selected on the basis of being immediately relevant to the topic of the workshop and of originating from a laboratory not represented by the main speakers. All in all we believe that the reader can get a fair idea of the structure and general character of this Workshop. The overall aim of the meeting was to review the current state of knowledge on the role of the superficial dorsal horn of the mammalian spinal cord as a nucleus of relay and modulation of the somatic and visceral sensory input to the central nervous system. In this context, the contribution of this spinal cord region to the appreciation of pain was a central topic of discussion. Over the last decade there has been a considerable increase in anatomical, physiological and neurochemical studies of the superficial dorsal horn.

Spinothalamic Tract Neurons in Laminae I III and IV of the Rat

Findings from the present study indicate that the PoT is one of the major targets for neurons in lamina I as well as to the population of the NK1r-immunoreactive neurons in laminae III and IV. Since the PoT projects to the second ...

Author: Khulood Al-Khater

Publisher:

ISBN: OCLC:757095317

Category:

Page: 256

View: 946

DOWNLOAD →

Ascending pathways in the spinal cord are very important in transmitting sensory information from the periphery to the higher brain centres. The spinothalamic tract represents an important component of these ascending pathways, and it has been traditionally described as the main pathway for conveying nociceptive and thermoceptive information. Spinothalamic neurons are widely distributed within the grey matter. Lamina I represents an important nociceptive zone and provides a significant source of projection neurons, some of which project to the thalamus. A projection from cervical superficial dorsal horn to the posterior triangular thalamic nucleus (PoT) in the rat has recently been identified. The PoT is located at the caudal end of the thalamus and was not included in injection sites in many previous quantitative retrograde tracing studies of the spinothalamic tract. Therefore, one of the reasons to conduct the present study was to estimate the number of the spinothalamic cells in lamina I in rat cervical and lumbar enlargements following injections that target the PoT with or without other thalamic nuclei known to receive input from lamina I. Neurons in this lamina are also known to project to the lateral parabrachial nucleus (LPb) and the periaqueductal grey matter (PAG). Other aims of the study were to quantify neurons in lamina I in the cervical enlargement that project to the LPb and PAG, to determine the proportion of lamina I spinothalamic neurons in lumbar and cervical enlargements that could be labelled from LPb and PAG, and to investigate morphological differences between different projection populations. Recent investigations have identified a group of neurons in lamina I of rat lumbar spinal cord that had large numbers of puncta that were immunoreactive for the glycine receptor-associated protein, gephyrin, and have a very high density of input from glutamatergic axons that contain vesicular glutamate transporter 2 (VGLUT2). These "large gephyrin-coated cells" in the lumbar cord are known to project to the LPb, but it is not yet known whether they project to thalamus and PAG. Therefore, another aim was to determine whether these cells project to these areas and also to analyse the projection pattern of cells of this type in the cervical enlargement. Previous studies have identified a population of large neurons in laminae III and IV of rat spinal cord that express the neurokinin 1 receptor (NK1r) and have prominent dorsal dendrites that enter the superficial laminae. A substantial body of evidence points to the involvement of this population of cells in processing various types of noxious stimulus. Neurons of this type in lumbar enlargement are projection cells and form a major route through which nociceptive information reaches the brain. The proportion of these neurons that project to thalamus was not previously known, and the projection pattern of cells of this type in cervical enlargement has not yet been investigated. Therefore, an additional aim was to elucidate more on the projection patterns of these cells in both enlargements. Various tracers (cholera toxin B subunit, Fluorogold or fluorescent latex microspheres) were injected stereotaxically into thalamus (25 rats), into thalamus and LPb (3 rats), or into thalamus and PAG (4 rats). Rats were perfused after three days and sections from the spinal cord (cervical and lumbar enlargements) were processed immunocytochemically to reveal tracer(s) in lamina I and lamina III/IV neurons, the NK1r, neuronal nuclei and, in some cases, the glycine receptor-associated protein gephyrin. Sections from brains were processed to visualise the injection sites. Results of this study showed that: 1) most lamina I spinothalamic neurons in the C7 and L4 segments could be labelled from injections centred on the PoT; 2) the estimated total numbers of spinothalamic cells in lamina I on the contralateral side of the C7 and L4 segments are 91 and 16 cells, respectively, and this constitutes 2-3% and 0.2% of the total neuronal population in lamina I in the C7 and L4 segments, respectively; 3) the C7 segment contained fewer lamina I spinoparabrachial cells, but a similar number of spino-PAG cells, compared to L4; 4) virtually all spinothalamic lamina I neurons at both cervical and lumbar levels were labelled from LPb and between a third and a half were labelled from PAG; 5) spinothalamic lamina I neurons differed from those labelled only from LPb in that they were generally larger, more often multipolar and (in cervical enlargement) had stronger NK1r-immunoreactivity; 6) ~39% of "large gephyrin-coated cells" in L5 project to the thalamus and this accounts for ~21% of the total thalamic projection from lamina I in this segment, even though these cells constitute only ~2.5% of projection neurons in lamina I; 7) the great majority of "large gephyrin-coated cells" in C6 project to thalamus and LPb, and at both segmental levels, some project to both of these areas; 8) only few "large gephyrin-coated cells" in L5 and some of those in C6 project to PAG; 9) ~84% of the lamina III/IV NK1r-immunoreactive neurons in C6 and C7 and 17 28% of those in L4 and L5 belong to the spinothalamic tract, and these apparently project exclusively to the caudal thalamus, including PoT; 10) most of the large NK1r-immunoreactive lamina III/IV cells at both levels project to LPb, but few were labelled from PAG, and at both segmental levels, some project to both thalamus and LPb. Findings from the present study indicate that the PoT is one of the major targets for neurons in lamina I as well as to the population of the NK1r-immunoreactive neurons in laminae III and IV. Since the PoT projects to the second somatosensory and insular cortices, the present results suggest that these are major targets for information conveyed by both these populations of spinothalamic neurons. In addition, these results confirm that projection neurons have extensive collateral projections, and suggest that different sub-populations of lamina I cell have characteristic patterns of supraspinal projection.

GPER GPR30 Estrogen Receptor

However, GPER involvement in pain processing at central levels is largely unexplored. Thus, the work presented in this thesis was aimed at investigating whether GPER modulates nociception at spinal and supraspinal sites.

Author: Elena Deliu

Publisher:

ISBN: OCLC:1285301526

Category:

Page: 135

View: 149

DOWNLOAD →

The G protein-coupled estrogen receptor GPER/GPER1, also known as GPR30, was originally cloned as an orphan receptor and later shown to be specifically activated by 17-ß-estradiol. This has led to its classification as an estrogen receptor and expanded the perspective on the mechanisms underlying the rapid estrogenic effects reported over the years. GPER is strongly expressed in the central nervous system and peripheral tissues and appears to be involved in a wide variety of physiological and pathological processes. Estrogens are known to alter the processing of nociceptive sensory information and analgesic responses in the central nervous system. Both analgesic and pro-nociceptive effects of estrogens have been reported. Some pro-algesic estrogenic responses have a short latency, suggesting a non-genomic mechanism of action. Immunohistochemical studies in rodents prove the existence of GPER in pain-relevant areas of the nervous system such as dorsal root ganglia, superficial dorsal horn of the spinal cord, periaqueductal gray (PAG), amygdala, trigeminal sensory nucleus and thalamus. In the periphery, activation of GPER results in pro-nociceptive effects. However, GPER involvement in pain processing at central levels is largely unexplored. Thus, the work presented in this thesis was aimed at investigating whether GPER modulates nociception at spinal and supraspinal sites. The behavioral response to GPER activation in the spinal cord and PAG was evaluated in an acute grooming test (scratching, biting and licking behavior) and in the hot plate test, respectively. Intrathecal challenge of mice with the GPER agonist G-1 (0.1-1 nmol) induced a dose-dependent increase in pain-related behaviors, that was abolished by pre-treatment with the GPER antagonist G15 (1-10 nmol), confirming GPER specificity of the response. Likewise, intra-PAG microinjection of G-1 (10-100 pmol) to rats reduced the nociceptive threshold in the hot plate test, an effect that was G15 sensitive. To obtain further insight on the mechanisms involved in the behavioral effects observed in whole animals, we tested the effect of GPER ligands on neuronal membrane potential, intracellular calcium concentration ([Ca2+]i) and reactive oxygen species (ROS) accumulation. The membrane depolarization and the increases in [Ca2+]i and ROS levels are markers of neuronal activation, underlying pain sensitization in the spinal cord and pain facilitation in the PAG. Electrophysiological recordings from superficial dorsal horn and lateral PAG neurons indicate neuronal depolarization upon G-1 application, an effect that was fully prevented by G15 pre-treatment. Both cultured spinal neurons and cultured PAG neurons responded to G-1 administration by elevating [Ca2+]i and mitochondrial and cytosolic ROS levels. In the presence of G15, G-1 did not elicit the calcium and ROS responses. Collectively, these results demonstrate that GPER modulates both the ascending and descending pain pathways to increase nociception via cytosolic calcium elevation and ROS accumulation in spinal and PAG neurons, respectively. These findings broaden the current knowledge on GPER involvement in physiology and pathophysiology, providing the first evidence of its pro-nociceptive effects at central levels and characterizing some of the mechanisms involved. Moreover, we show for the first time ROS accumulation downstream of GPER activation, extending the current understanding of GPER signaling.

Transplantation of Neural Tissue into the Spinal Cord

Processing of Sensory Information in the Superficial Dorsal Horn of the Spinal Cord. New York and London: Plenum Press, 1988:199-215. Lima D, Coimbra A. Morphological types of spinomesencephalic neurons in the marginal zone (lamina I) ...

Author: Antal Nogradi

Publisher: Springer Science & Business Media

ISBN: 9780387326337

Category: Medical

Page: 150

View: 232

DOWNLOAD →

The book gives an account of results obtained from experiments where grafts of neuronal, glial and other tissues as well as artificial materials were placed into the spinal cord. It attempts to evaluate the contributions made by these studies to our understanding of basic neurobiologies questions. These include factors that regulate neuronal growth during development as well as regenera tion following injury to the nervous system. The model of neural transplanta tion is also useful for the study of cell-to-cell interactions, and this applies to interactions between glial cells and neurones, between various populations of neuronal cells and finally between axons and skeletal muscle fibres. The mecha nisms involved in the establishment of specific synaptic connections between neurones can also be investigated in this experimental paradigm. Important in formation regarding this issue was also obtained on systems other than the spinal cord, i. e. the cerebellum, hippocampus and striatum. Although such in formation of precise connections between the host and the grafted embryonic tissue is still lacking in the spinal cord, there is much information on the re sponse of the host nervous system to the grafted embryonic tissue, and that of the graft to its new host environment. It appears that embryonic grafts are able to induce repair processes follow ing injury to the nervous system.

Scientific Directory and Annual Bibliography

Processing of sensory information in the superficial dorsal horn of the spinal cord . New York : 4811. Prabhakar BS , Allaway GP , Srinivasappa J , Notkins AL . Cell Plenum , 1989 ; 463-72 . surface expression of the 70 - kD component ...

Author: National Institutes of Health (U.S.)

Publisher:

ISBN: MINN:31951D008755076

Category: Biochemistry

Page:

View: 120

DOWNLOAD →

Presents the broad outline of NIH organizational structure, theprofessional staff, and their scientific and technical publications covering work done at NIH.

Sensory Mechanisms of the Spinal Cord

Volume 1 Primary Afferent Neurons and the Spinal Dorsal Horn William D. Willis Jr., Richard E. Coggeshall ... Processing of Sensory Information in the Superficial Dorsal Horn of the Spinal Cord ( pp . 199–213 ) .

Author: William D. Willis Jr.

Publisher: Springer Science & Business Media

ISBN: 0306480336

Category: Medical

Page: 581

View: 819

DOWNLOAD →

The third edition of this monograph continues to have the goal of providing an overview of current thought about the spinal cord mechanisms that are responsible for sensory processing. We hope that the book is of value to both basic and clinical neuroscientists. Several changes have been made in the presentation, as well as additions because of the research advances that have been made during the past decade. Chapters 3 and 4 in the previous edition have been subdivided, and now the morphology of primary afferent neu rons of the dorsal root ganglia is described in Chapter 3 and the chemical neuroanatomy 4. The description of the dorsal hom in the previous Chapter 4 of these neurons in Chapter is now included in Chapter 5, and the chemical neuroanatomy of the dorsal hom in Chapter 6. Furthermore, discussions of the descending control systems have now been of Chapter 12. consolidated at the end The authors would like to express their appreciation for the help provided by several individuals. R.E.C. wishes to acknowledge the many things he learned about primary afferent neurons from conversations with Dr S. N. Lawson. He also thanks Lyn Shilling for her assistance with the typing. WDW thanks Dr Nada Lawand for her critical reading of parts of the manuscript, Rosaline Leigh for help with the manuscript, and Griselda Gonzales for preparing the illustrations.

Neuropeptides in the Spinal Cord

Ardvidsson, J. and Pfaller, K. (1990) Central projections of C4-C8 dorsal root ganglia in the rat studied by anterograde ... Processing of Sensory Information in the Superficial Dorsal Horn of the Spinal Cord, NATO Asi Series, Vol.

Author: F. Nyberg

Publisher: Elsevier

ISBN: 9780080862293

Category: Science

Page: 418

View: 611

DOWNLOAD →

This is the first book devoted exclusively to examining the role of neuropeptides in the spinal cord. Great progress has been made recently in our understanding of the role of neuropeptides in neurotransmission. New tools have been developed to help study the function of endogenous neuropeptides in health and disease. Because the general organization of the spinal cord is well conserved among species and neuropeptides appear to have a major role in spinal neurotransmission, this book is a timely compendium of recent research in this field. The volume will help to stimulate further research in the field of neuropeptides which will lead to better understanding of this role in health and disease.

Handbook of Brain Microcircuits

... ascending tract projection neurons and non-tract neurons in the superficial dorsal horn (SDH). In: Cervero F, Bennett GJ and Headley PM, eds. Processing of Sensory Information in the Superficial Dorsal Horn of the Spinal Cord, pp.

Author: Gordon Shepherd, Sten Grillner

Publisher: Oxford University Press

ISBN: 9780199780334

Category: Medical

Page: 536

View: 291

DOWNLOAD →

Microcircuits are the specific arrangements of cells and their connections that carry out the operations unique to each brain region. This resource summarizes succinctly these circuits in over 40 regions - enabling comparisons of principles across both vertebrates and invertebrates. It provides a new foundation for understanding brain function that will be of interest to all neuroscientists. Oxford Clinical Neuroscience is a comprehensive, cross-searchable collection of resources offering quick and easy access to eleven of Oxford University Press's prestigious neuroscience texts. Joining Oxford Medicine Online these resources offer students, specialists and clinical researchers the best quality content in an easy-to-access format.

Mechanisms and Mediators of Neuropathic Pain

In : Cervero F , Bennett GJ , Headley PM ( eds ) : Processing of sensory information in the superficial dorsal horn of the spinal cord . Plenum Press , New York , 463-471 26 Sugimoto T , Bennett GJ , Kajander KC ( 1990 ) Transsynaptic ...

Author: Annika B. Malmberg

Publisher: Springer Science & Business Media

ISBN: 3764362375

Category: Medical

Page: 260

View: 597

DOWNLOAD →

Numerous improvements in our understanding of the mechanisms that underlie neuropathic pain states have come from the development of animal models, most of which involve partial peripheral nerve injury. The animal models have shown that nerve injury initiates a cascade of events resulting in altered neurochemistry and molecular biology of the peripheral neurons, the dorsal root ganglion cell, and changes in neurotransmitter and receptor expression in the dorsal horn of the spinal cord. Moreover, nerve injury produces anatomical changes with functional consequences. This volume summarises the current understanding of the pathophysiological processes in the peripheral and central nervous system that contribute to the neuropathic pain. It provides a timely review of neuropathic pain mechanisms, written by experts in the field.

The Perplexing Physiology of the Nociceptive System

FIGURE 1 | Historical models of spinal pain processing. (A), schematic shows the originally proposed circuitry for the Gate Control Theory of Pain. Touch related sensory information is relayed to the dorsal horn by large fiber ...

Author: Istvan Nagy

Publisher: Frontiers Media SA

ISBN: 9782889740277

Category: Science

Page:

View: 121

DOWNLOAD →

Impacts that threaten or indeed compromise the integrity of tissues trigger the development of a defence response, which through the activity of the nociceptive system includes pain. If the noxious impact does not induce tissue damage, the pain, called “nociceptive” pain, ceases within seconds after the impact is withdrawn. In contrast, if tissue damage does occur, a pain experience that usually persists until the injury is resolved and includes two major pathological sensory experiences, hypersensitivity to heat stimuli (i.e. heat hyperalgesia) and/or hypersensitivity to mechanical stimuli (i.e. mechanical allodynia) develop. The cellular and molecular mechanisms underlying the development of nociceptive pain are fairly well understood. Our understanding of the development of pain associated with tissue injury has also significantly improved in the last decades. Hence, two fundamental mechanisms, interactions between the nervous and immune systems both within and without the central nervous system and sensitization that is a use-dependent increase in the sensitivity and activity of neurons involved in nociceptive processing have been identified being pivotal for the development of tissue injury-associated pain. However, important details of the cellular and molecular mechanisms, which account for the development of the pathological sensory experiences and those experiences becoming persistent, still await elucidation.