Author: Amanda C. ContaPublisher:
ISBN:
Category :
Languages : en
Pages : 508
Book Description
Effects of Spinal Cord Contusion Injury on Rat Propriospinal Neurons
Author: Amanda C. ContaPropriospinal Neurons: Essential Elements in Locomotion, Autonomic Function and Plasticity after Spinal Cord Injury and Disease
Author: Katinka StecinaPublisher: Frontiers Media SA
ISBN: 2889669165
Category : Science
Languages : en
Pages : 177
Book Description
Modelling of Spinal Cord Injury in the Rat
Author: Donald Lee BehrmannEffects of Red Light Treatment on Spinal Cord Injury in Rats
Author: Di HuPublisher:
ISBN:
Category :
Languages : en
Pages : 0
Book Description
Spinal cord injury can cause detrimental damage or complete loss in sensory and motor function. Current treatments, such as pharmaceutical interventions and physical therapy, provide limited improvements to restoring sensorimotor function following spinal cord injury. A non-conventional treatment using light irradiation in the red to near infrared range has been shown to promote recovery in a variety of injuries and conditions including spinal cord injury. This thesis examines the effects of red (670 nm) light irradiation on sensorimotor recovery following a mild T10 hemicontusion spinal cord injury in rats. To demonstrate that this treatment could potentially access the human cord, the penetration of 670 nm irradiation in different human tissues in both human participants and cadavers were examined. 670 nm irradiation with a light emitting diode (LED) at an intensity of 100 mW/cm2 was shown to penetrate 50 mm of human tissue, independent of skin tone, indicating that red light treatment could reach the spinal cord of humans with intensities ≥ 100 mW/cm2. Following spinal cord injury in rats, the development of mechanical hypersensitivity, the functional integrity of dorsal column pathways (measured from surface field potential electrophysiology recording) and locomotor function (evaluated from the Basso, Beattie and Bresnahan locomotor test), together with cellular changes in the spinal cord (evaluated from immunohistochemistry) were investigated. Animals with spinal cord injury were separated into hypersensitive and normosensitive subpopulations based on their mechanical sensitivity. Daily 30 min 670 nm irradiation (35 mW/cm2) is effective at reducing the chance of developing mechanical hypersensitivity following spinal cord injury, as well as reducing the mechanical sensitivity in the normosensitive subpopulation from 1-day, and the hypersensitive subpopulation from 7-days post-injury. The treatment also improves sensory conduction along the dorsal column pathway and accelerates locomotor recovery. These functional improvements are accompanied with: an overall reduction of microglial/macrophage activation, but a specific increase in the proportion of the anti-inflammatory subtype; reduced astrocyte reactivity; reduced iNOS expressing microglia/macrophages; and reduced density of cells undergoing apoptosis/necrosis. Together, the findings in this thesis highlight the potential for the use of red light as a non-invasive and inexpensive treatment/adjunct therapy for spinal cord injured patients.
Modeling and Treatment of Rat Cervical Spinal Cord Injury
Author: John Carib GenselPublisher:
ISBN:
Category : Bruises
Languages : en
Pages : 200
Book Description
Abstract: Spinal cord injury (SCI) is a long lasting, debilitating condition with no cure. Cervical SCI is the most common form of human SCI, often leaving patients paralyzed with a 15-20 year decrease in life expectancy. The majority of animal SCI contusion models are focused on thoracic injury. SCI at this level results in deficits almost entirely due to white matter damage that disconnects the rostral nervous system from the caudal spinal cord. Damage at the cervical level is different; in addition to the disconnection, gray matter damage affects the neurons controlling the upper extremities and diaphragm. To investigate injury at the cervical level, we characterized a unilateral C5 cervical contusion model in rats. By examining six-week behavioral recovery after SCI, we demonstrated that functional deficits are dependent upon the severity of injury. Analysis of the histopathology revealed that behavioral consequences are a result of damage to both the gray and white matter. Unilateral injury provides within-subject controls and preserves bladder and respiratory function. Many treatments for experimental rat SCI improve behavioral and histological outcomes but have yet to be implemented after human SCI. Treatments must be safe and tested in clinically relevant models to move from animals to humans. We examined the effects of three different clinically acceptable drugs. Methlyprednisolone and minocycline have anti-inflammatory effects if given after injury. Topiramate blocks glutamate receptors and hence excitotoxicity, an important component of secondary injury. Minocycline and methylprednisolone treatment yielded no significant behavioral or histological improvements when tested after moderate-severe unilateral cervical contusion injury. Topiramate was first tested in a model of excitotoxicity and then after cervical SCI and was compared to NBQX, a standard AMPA-receptor antagonists used in animal models of disease. Both drugs preserved neurons after excitotoxic injury, but only topiramate was found to protect neurons after SCI. More small and medium sized neurons were spared in the topiramate treated group compared to control 48 hours after SCI. NBQX treatment increased white matter sparing compared to control, but resulted in worse motor function compared to topiramate. Both treatments were only effective when applied after moderate-severe injury and not after mild injury.
The Recovery of Function After Spinal Cord Contusion Injury in Rats
Author: Karen J. HutchinsonThe Role of C3-C4 Propriospinal Interneurons on Reaching and Grasping Behaviors Pre- and Post-Cervical Spinal Cord Injury
Author: Imran Sana SheikhPublisher:
ISBN:
Category :
Languages : en
Pages : 179
Book Description
Greater than 50% of all spinal cord injuries (SCIs) in humans occur at the cervical level and the biggest desire of quadriplegic patients is recovery of hand and digit function. Several weeks after spinal cord injury, re-organization and re-modeling of spared endogenous pathways occurs and plasticity of both supraspinal and interneuronal networks are believed to mediate functional recovery. Propriospinal interneurons (PNs) are neurons found entirely in the spinal cord with axons projecting to different spinal segments. PNs function by modulating locomotion, integrating supraspinal motor pathways and peripheral sensory afferents. Recent studies have postulated that if PNs are spared following SCI, these neurons can contribute to functional recovery by establishing synaptic connections onto motor neurons. However, to what extent cervical PNs are involved in recovery of reaching behavior is not known. In our first study, we generated a lentiviral vector that permits highly efficient retrograde transport (HiRet) upon uptake at synaptic terminals in order to map supraspinal and interneuronal populations terminating near forelimb motoneurons (MNs) innervating the limb. With this vector, we found neurons labeled within the C3-C4 spinal cord and in the red nucleus, two major populations which are known to modulate forelimb reaching behavior. We also proceeded to use a novel two-viral vector method to specifically label ipsilateral C3-C4 PNs with tetracycline-inducible GFP. Histological analysis showed detailed labeling of somas, dendrites along with axon terminals. Based on this data, we proceeded to determine the contribution of C3-C4 PNs and rubrospinal neurons on forelimb reaching and grasping before and after cervical SCI. In our second study, we have examined a double-infection technique for shutdown of PNs and rubrospinal neurons (RSNs) in adult rats. Adult rats were microinjected with a lentiviral vector expressing tetracycline-inducible inhibitory DREADDs into C6-T1 spinal levels. Adeno-associated viral vectors (AAV2) expressing TetON mixed with GIRK2 were injected into the red nucleus and C3-C4 spinal levels respectively. Rats were tested for deficits in reaching behaviors upon application of doxycycline and clozapine-n-oxide (CNO) administration. No behavioral deficits were observed pre-injury. Rats then received a C5 spinal cord lesion to sever cortical input to forelimb motoneurons and were allowed four weeks to spontaneously recover. Upon re-administration of CNO to activate inhibitory DREADDs, deficits were observed in forelimb reaching. Histological analysis of the C3-C4 spinal cord and red nucleus showed DREADD+ neurons co-expressing GIRK2 in somas and dendrites of PNs and RSNs. PN terminals expressing DREADD were observed near C6-T1 motoneurons and in the brainstem. Control animals did not show substantial deficits with CNO administration. These results indicate both rubro- and propriospinal pathways are necessary for recovery of forelimb reaching. In a separate study, we sought to determine if promoting severed CST sprouting rostral to a C5 lesion near C3-C4 PNs could improve behavioral recovery post SCI. Past studies have examined sprouting and regeneration of corticospinal tract (CST) fibers post-cervical SCI through viral upregulation of key components of the PI3K/Akt/mTOR cascade. We examined the regenerative growth potential of CST fibers that are transduced with AAV2 expressing constituively active Akt3 or STAT3 both separately and in combination (Akt3 + STAT3). We have observed significant increases in CST axonal sprouting and regeneration in Akt3 and Akt3 + STAT3 transduced samples. However, no recovery was observed as animals transduced with viral constitutively active Akt3 displayed an epileptic phenotype. Further, epileptic animals with constitutively active Akt3 were found to have significant cortical neuron cell hypertrophy, activatived astrogliosis, increased dendritic arbors and hemimegencephalitis (HME). These results indicate a new model for examining mechanisms of HME and mTOR hyperactivity-induced epilepsy in adult rodents.
The Spinal Cord
Author: Charles WatsonPublisher: Academic Press
ISBN: 0080921388
Category : Medical
Languages : en
Pages : 408
Book Description
Many hundreds of thousands suffer spinal cord injuries leading to loss of sensation and motor function in the body below the point of injury. Spinal cord research has made some significant strides towards new treatment methods, and is a focus of many laboratories worldwide. In addition, research on the involvement of the spinal cord in pain and the abilities of nervous tissue in the spine to regenerate has increasingly been on the forefront of biomedical research in the past years. The Spinal Cord, a collaboration with the Christopher and Dana Reeve Foundation, is the first comprehensive book on the anatomy of the mammalian spinal cord. Tens of thousands of articles and dozens of books are published on this subject each year, and a great deal of experimental work has been carried out on the rat spinal cord. Despite this, there is no comprehensive and authoritative atlas of the mammalian spinal cord. Almost all of the fine details of spinal cord anatomy must be searched for in journal articles on particular subjects. This book addresses this need by providing both a comprehensive reference on the mammalian spinal cord and a comparative atlas of both rat and mouse spinal cords in one convenient source. The book provides a descriptive survey of the details of mammalian spinal cord anatomy, focusing on the rat with many illustrations from the leading experts in the field and atlases of the rat and the mouse spinal cord. The rat and mouse spinal cord atlas chapters include photographs of Nissl stained transverse sections from each of the spinal cord segments (obtained from a single unfixed spinal cord), detailed diagrams of each of the spinal cord segments pictured, delineating the laminae of Rexed and all other significant neuronal groupings at each level and photographs of additional sections displaying markers such as acetylcholinesterase (AChE), calbindin, calretinin, choline acetlytransferase, neurofilament protein (SMI 32), enkephalin, calcitonin gene-related peptide (CGRP), and neuronal nuclear protein (NeuN). The text provides a detailed account of the anatomy of the mammalian spinal cord and surrounding musculoskeletal elements The major topics addressed are: development of the spinal cord; the gross anatomy of the spinal cord and its meninges; spinal nerves, nerve roots, and dorsal root ganglia; the vertebral column, vertebral joints, and vertebral muscles; blood supply of the spinal cord; cytoarchitecture and chemoarchitecture of the spinal gray matter; musculotopic anatomy of motoneuron groups; tracts connecting the brain and spinal cord; spinospinal pathways; sympathetic and parasympathetic elements in the spinal cord; neuronal groups and pathways that control micturition; the anatomy of spinal cord injury in experimental animals The atlas of the rat and mouse spinal cord has the following features: Photographs of Nissl stained transverse sections from each of 34 spinal segments for the rat and mouse; Detailed diagrams of each of the 34 spinal segments for rat and mouse, delineating the laminae of Rexed and all other significant neuronal groupings at each level. ; Alongside each of the 34 Nissl stained segments, there are additional sections displaying markers such as acetylcholinesterase, calbindin, calretinin, choline acetlytransferase, neurofilament protein (SMI 32), and neuronal nuclear protein (NeuN) All the major motoneuron clusters are identified in relation to the individual muscles or muscle groups they supply
Neurotrauma
Author: Raj K. NarayanPublisher: McGraw-Hill
ISBN: 9780070456624
Category : Medical
Languages : en
Pages : 1558
Book Description
This reference is a comprehensive work in the field of neurotrauma and critical care. It incorporates the fields of head injury, spinal injury and basic neurotrauma research into one source. The major emphasis is on the treatment of patients with head and spinal cord injury, including the management of all other problems that bear upon the care of these patients.
Neuroanatomical Tract-Tracing
Author: Laszlo ZaborszkyPublisher: Springer Science & Business Media
ISBN: 0387289429
Category : Medical
Languages : en
Pages : 703
Book Description
The first two editions of this title had a tremendous impact in neuroscience. Between the Second edition in 1989 and today, there has been an explosion of information in the field, including advances in molecular techniques, such as genomics and proteomics, which have become increasing important in neuroscience. A renaissance in fluorescence has occurred, driven by the development of new probes, new microscopes, live imagers, and computer processing. The introduction of new markers has enormously stimulated the field, moving it from tissue culture to neurophysiology to functional MRI techniques.