Spinal Cord: A cylindrical column of tissue that lies within the vertebral canal. It is composed of WHITE MATTER and GRAY MATTER.Spinal Cord Injuries: Penetrating and non-penetrating injuries to the spinal cord resulting from traumatic external forces (e.g., WOUNDS, GUNSHOT; WHIPLASH INJURIES; etc.).Spinal Cord Diseases: Pathologic conditions which feature SPINAL CORD damage or dysfunction, including disorders involving the meninges and perimeningeal spaces surrounding the spinal cord. Traumatic injuries, vascular diseases, infections, and inflammatory/autoimmune processes may affect the spinal cord.Spinal Cord Compression: Acute and chronic conditions characterized by external mechanical compression of the SPINAL CORD due to extramedullary neoplasm; EPIDURAL ABSCESS; SPINAL FRACTURES; bony deformities of the vertebral bodies; and other conditions. Clinical manifestations vary with the anatomic site of the lesion and may include localized pain, weakness, sensory loss, incontinence, and impotence.Spinal Cord Neoplasms: Benign and malignant neoplasms which occur within the substance of the spinal cord (intramedullary neoplasms) or in the space between the dura and spinal cord (intradural extramedullary neoplasms). The majority of intramedullary spinal tumors are primary CNS neoplasms including ASTROCYTOMA; EPENDYMOMA; and LIPOMA. Intramedullary neoplasms are often associated with SYRINGOMYELIA. The most frequent histologic types of intradural-extramedullary tumors are MENINGIOMA and NEUROFIBROMA.Spinal Cord Ischemia: Reduced blood flow to the spinal cord which is supplied by the anterior spinal artery and the paired posterior spinal arteries. This condition may be associated with ARTERIOSCLEROSIS, trauma, emboli, diseases of the aorta, and other disorders. Prolonged ischemia may lead to INFARCTION of spinal cord tissue.Injections, Spinal: Introduction of therapeutic agents into the spinal region using a needle and syringe.Paraplegia: Severe or complete loss of motor function in the lower extremities and lower portions of the trunk. This condition is most often associated with SPINAL CORD DISEASES, although BRAIN DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; and MUSCULAR DISEASES may also cause bilateral leg weakness.Spinal Nerve Roots: Paired bundles of NERVE FIBERS entering and leaving the SPINAL CORD at each segment. The dorsal and ventral nerve roots join to form the mixed segmental spinal nerves. The dorsal roots are generally afferent, formed by the central projections of the spinal (dorsal root) ganglia sensory cells, and the ventral roots are efferent, comprising the axons of spinal motor and PREGANGLIONIC AUTONOMIC FIBERS.Spinal Nerves: The 31 paired peripheral nerves formed by the union of the dorsal and ventral spinal roots from each spinal cord segment. The spinal nerve plexuses and the spinal roots are also included.Motor Neurons: Neurons which activate MUSCLE CELLS.Spinal Cord Regeneration: Repair of the damaged neuron function after SPINAL CORD INJURY or SPINAL CORD DISEASES.Spinal Canal: The cavity within the SPINAL COLUMN through which the SPINAL CORD passes.Spinal NeoplasmsCervical Vertebrae: The first seven VERTEBRAE of the SPINAL COLUMN, which correspond to the VERTEBRAE of the NECK.Anesthesia, Spinal: Procedure in which an anesthetic is injected directly into the spinal cord.Quadriplegia: Severe or complete loss of motor function in all four limbs which may result from BRAIN DISEASES; SPINAL CORD DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; or rarely MUSCULAR DISEASES. The locked-in syndrome is characterized by quadriplegia in combination with cranial muscle paralysis. Consciousness is spared and the only retained voluntary motor activity may be limited eye movements. This condition is usually caused by a lesion in the upper BRAIN STEM which injures the descending cortico-spinal and cortico-bulbar tracts.Thoracic Vertebrae: A group of twelve VERTEBRAE connected to the ribs that support the upper trunk region.Spinal DiseasesUmbilical Cord: The flexible rope-like structure that connects a developing FETUS to the PLACENTA in mammals. The cord contains blood vessels which carry oxygen and nutrients from the mother to the fetus and waste products away from the fetus.Posterior Horn Cells: Neurons in the SPINAL CORD DORSAL HORN whose cell bodies and processes are confined entirely to the CENTRAL NERVOUS SYSTEM. They receive collateral or direct terminations of dorsal root fibers. They send their axons either directly to ANTERIOR HORN CELLS or to the WHITE MATTER ascending and descending longitudinal fibers.Laminectomy: A surgical procedure that entails removing all (laminectomy) or part (laminotomy) of selected vertebral lamina to relieve pressure on the SPINAL CORD and/or SPINAL NERVE ROOTS. Vertebral lamina is the thin flattened posterior wall of vertebral arch that forms the vertebral foramen through which pass the spinal cord and nerve roots.Rats, Sprague-Dawley: A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company.Lumbosacral Region: Region of the back including the LUMBAR VERTEBRAE, SACRUM, and nearby structures.Recovery of Function: A partial or complete return to the normal or proper physiologic activity of an organ or part following disease or trauma.Nerve Regeneration: Renewal or physiological repair of damaged nerve tissue.Axons: Nerve fibers that are capable of rapidly conducting impulses away from the neuron cell body.Spinal Stenosis: Narrowing of the spinal canal.Ganglia, Spinal: Sensory ganglia located on the dorsal spinal roots within the vertebral column. The spinal ganglion cells are pseudounipolar. The single primary branch bifurcates sending a peripheral process to carry sensory information from the periphery and a central branch which relays that information to the spinal cord or brain.Spinal Cord Stimulation: Application of electric current to the spine for treatment of a variety of conditions involving innervation from the spinal cord.Locomotion: Movement or the ability to move from one place or another. It can refer to humans, vertebrate or invertebrate animals, and microorganisms.Spinal Fusion: Operative immobilization or ankylosis of two or more vertebrae by fusion of the vertebral bodies with a short bone graft or often with diskectomy or laminectomy. (From Blauvelt & Nelson, A Manual of Orthopaedic Terminology, 5th ed, p236; Dorland, 28th ed)Spinal Injuries: Injuries involving the vertebral column.Anterior Horn Cells: MOTOR NEURONS in the anterior (ventral) horn of the SPINAL CORD which project to SKELETAL MUSCLES.Myelitis: Inflammation of the spinal cord. Relatively common etiologies include infections; AUTOIMMUNE DISEASES; SPINAL CORD; and ischemia (see also SPINAL CORD VASCULAR DISEASES). Clinical features generally include weakness, sensory loss, localized pain, incontinence, and other signs of autonomic dysfunction.Cordotomy: Any operation on the spinal cord. (Stedman, 26th ed)Paralysis: A general term most often used to describe severe or complete loss of muscle strength due to motor system disease from the level of the cerebral cortex to the muscle fiber. This term may also occasionally refer to a loss of sensory function. (From Adams et al., Principles of Neurology, 6th ed, p45)Muscular Atrophy, Spinal: A group of disorders marked by progressive degeneration of motor neurons in the spinal cord resulting in weakness and muscular atrophy, usually without evidence of injury to the corticospinal tracts. Diseases in this category include Werdnig-Hoffmann disease and later onset SPINAL MUSCULAR ATROPHIES OF CHILDHOOD, most of which are hereditary. (Adams et al., Principles of Neurology, 6th ed, p1089)Pain: An unpleasant sensation induced by noxious stimuli which are detected by NERVE ENDINGS of NOCICEPTIVE NEURONS.Neurons: The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.Hyperalgesia: An increased sensation of pain or discomfort produced by mimimally noxious stimuli due to damage to soft tissue containing NOCICEPTORS or injury to a peripheral nerve.Electric Stimulation Therapy: Application of electric current in treatment without the generation of perceptible heat. It includes electric stimulation of nerves or muscles, passage of current into the body, or use of interrupted current of low intensity to raise the threshold of the skin to pain.Neuralgia: Intense or aching pain that occurs along the course or distribution of a peripheral or cranial nerve.Disease Models, Animal: Naturally occurring or experimentally induced animal diseases with pathological processes sufficiently similar to those of human diseases. They are used as study models for human diseases.Myelography: X-ray visualization of the spinal cord following injection of contrast medium into the spinal arachnoid space.Electric Stimulation: Use of electric potential or currents to elicit biological responses.Spine: The spinal or vertebral column.Epidural Space: Space between the dura mater and the walls of the vertebral canal.Afferent Pathways: Nerve structures through which impulses are conducted from a peripheral part toward a nerve center.Urinary Bladder, Neurogenic: Dysfunction of the URINARY BLADDER due to disease of the central or peripheral nervous system pathways involved in the control of URINATION. This is often associated with SPINAL CORD DISEASES, but may also be caused by BRAIN DISEASES or PERIPHERAL NERVE DISEASES.Hematoma, Epidural, Spinal: A rare epidural hematoma in the spinal epidural space, usually due to a vascular malformation (CENTRAL NERVOUS SYSTEM VASCULAR MALFORMATIONS) or TRAUMA. Spontaneous spinal epidural hematoma is a neurologic emergency due to a rapidly evolving compressive MYELOPATHY.Hindlimb: Either of two extremities of four-footed non-primate land animals. It usually consists of a FEMUR; TIBIA; and FIBULA; tarsals; METATARSALS; and TOES. (From Storer et al., General Zoology, 6th ed, p73)Neurons, Afferent: Neurons which conduct NERVE IMPULSES to the CENTRAL NERVOUS SYSTEM.Nociceptors: Peripheral AFFERENT NEURONS which are sensitive to injuries or pain, usually caused by extreme thermal exposures, mechanical forces, or other noxious stimuli. Their cell bodies reside in the DORSAL ROOT GANGLIA. Their peripheral terminals (NERVE ENDINGS) innervate target tissues and transduce noxious stimuli via axons to the CENTRAL NERVOUS SYSTEM.Lumbar Vertebrae: VERTEBRAE in the region of the lower BACK below the THORACIC VERTEBRAE and above the SACRAL VERTEBRAE.Reflex: An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Lampreys: Common name for the only family (Petromyzontidae) of eellike fish in the order Petromyzontiformes. They are jawless but have a sucking mouth with horny teeth.Motor Activity: The physical activity of a human or an animal as a behavioral phenomenon.Autonomic Dysreflexia: A syndrome associated with damage to the spinal cord above the mid thoracic level (see SPINAL CORD INJURIES) characterized by a marked increase in the sympathetic response to minor stimuli such as bladder or rectal distention. Manifestations include HYPERTENSION; TACHYCARDIA (or reflex bradycardia); FEVER; FLUSHING; and HYPERHIDROSIS. Extreme hypertension may be associated with a STROKE. (From Adams et al., Principles of Neurology, 6th ed, pp538 and 1232; J Spinal Cord Med 1997;20(3):355-60)Interneurons: Most generally any NEURONS which are not motor or sensory. Interneurons may also refer to neurons whose AXONS remain within a particular brain region in contrast to projection neurons, which have axons projecting to other brain regions.Pyramidal Tracts: Fibers that arise from cells within the cerebral cortex, pass through the medullary pyramid, and descend in the spinal cord. Many authorities say the pyramidal tracts include both the corticospinal and corticobulbar tracts.Electromyography: Recording of the changes in electric potential of muscle by means of surface or needle electrodes.Magnetic Resonance Imaging: Non-invasive method of demonstrating internal anatomy based on the principle that atomic nuclei in a strong magnetic field absorb pulses of radiofrequency energy and emit them as radiowaves which can be reconstructed into computerized images. The concept includes proton spin tomographic techniques.Pain Measurement: Scales, questionnaires, tests, and other methods used to assess pain severity and duration in patients or experimental animals to aid in diagnosis, therapy, and physiological studies.Tuberculosis, Spinal: Osteitis or caries of the vertebrae, usually occurring as a complication of tuberculosis of the lungs.Myelin Sheath: The lipid-rich sheath surrounding AXONS in both the CENTRAL NERVOUS SYSTEMS and PERIPHERAL NERVOUS SYSTEM. The myelin sheath is an electrical insulator and allows faster and more energetically efficient conduction of impulses. The sheath is formed by the cell membranes of glial cells (SCHWANN CELLS in the peripheral and OLIGODENDROGLIA in the central nervous system). Deterioration of the sheath in DEMYELINATING DISEASES is a serious clinical problem.Cats: The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)Central Nervous System: The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges.Fetal Blood: Blood of the fetus. Exchange of nutrients and waste between the fetal and maternal blood occurs via the PLACENTA. The cord blood is blood contained in the umbilical vessels (UMBILICAL CORD) at the time of delivery.Physical Stimulation: Act of eliciting a response from a person or organism through physical contact.Neuroglia: The non-neuronal cells of the nervous system. They not only provide physical support, but also respond to injury, regulate the ionic and chemical composition of the extracellular milieu, participate in the BLOOD-BRAIN BARRIER and BLOOD-RETINAL BARRIER, form the myelin insulation of nervous pathways, guide neuronal migration during development, and exchange metabolites with neurons. Neuroglia have high-affinity transmitter uptake systems, voltage-dependent and transmitter-gated ion channels, and can release transmitters, but their role in signaling (as in many other functions) is unclear.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Contusions: Injuries resulting in hemorrhage, usually manifested in the skin.Evoked Potentials, Somatosensory: The electric response evoked in the CEREBRAL CORTEX by stimulation along AFFERENT PATHWAYS from PERIPHERAL NERVES to CEREBRUM.Brain Stem: The part of the brain that connects the CEREBRAL HEMISPHERES with the SPINAL CORD. It consists of the MESENCEPHALON; PONS; and MEDULLA OBLONGATA.Spinal Curvatures: Deformities of the SPINE characterized by abnormal bending or flexure in the vertebral column. They may be bending forward (KYPHOSIS), backward (LORDOSIS), or sideway (SCOLIOSIS).Oligodendroglia: A class of large neuroglial (macroglial) cells in the central nervous system. Oligodendroglia may be called interfascicular, perivascular, or perineuronal (not the same as SATELLITE CELLS, PERINEURONAL of GANGLIA) according to their location. They form the insulating MYELIN SHEATH of axons in the central nervous system.Spermatic Cord: Either of a pair of tubular structures formed by DUCTUS DEFERENS; ARTERIES; VEINS; LYMPHATIC VESSELS; and nerves. The spermatic cord extends from the deep inguinal ring through the INGUINAL CANAL to the TESTIS in the SCROTUM.Sciatic Nerve: A nerve which originates in the lumbar and sacral spinal cord (L4 to S3) and supplies motor and sensory innervation to the lower extremity. The sciatic nerve, which is the main continuation of the sacral plexus, is the largest nerve in the body. It has two major branches, the TIBIAL NERVE and the PERONEAL NERVE.Syringomyelia: Longitudinal cavities in the spinal cord, most often in the cervical region, which may extend for multiple spinal levels. The cavities are lined by dense, gliogenous tissue and may be associated with SPINAL CORD NEOPLASMS; spinal cord traumatic injuries; and vascular malformations. Syringomyelia is marked clinically by pain and PARESTHESIA, muscular atrophy of the hands, and analgesia with thermoanesthesia of the hands and arms, but with the tactile sense preserved (sensory dissociation). Lower extremity spasticity and incontinence may also develop. (From Adams et al., Principles of Neurology, 6th ed, p1269)Muscle Spasticity: A form of muscle hypertonia associated with upper MOTOR NEURON DISEASE. Resistance to passive stretch of a spastic muscle results in minimal initial resistance (a "free interval") followed by an incremental increase in muscle tone. Tone increases in proportion to the velocity of stretch. Spasticity is usually accompanied by HYPERREFLEXIA and variable degrees of MUSCLE WEAKNESS. (From Adams et al., Principles of Neurology, 6th ed, p54)Efferent Pathways: Nerve structures through which impulses are conducted from a nerve center toward a peripheral site. Such impulses are conducted via efferent neurons (NEURONS, EFFERENT), such as MOTOR NEURONS, autonomic neurons, and hypophyseal neurons.Strychnine: An alkaloid found in the seeds of STRYCHNOS NUX-VOMICA. It is a competitive antagonist at glycine receptors and thus a convulsant. It has been used as an analeptic, in the treatment of nonketotic hyperglycinemia and sleep apnea, and as a rat poison.Cauda Equina: The lower part of the SPINAL CORD consisting of the lumbar, sacral, and coccygeal nerve roots.Spinal Muscular Atrophies of Childhood: A group of recessively inherited diseases that feature progressive muscular atrophy and hypotonia. They are classified as type I (Werdnig-Hoffman disease), type II (intermediate form), and type III (Kugelberg-Welander disease). Type I is fatal in infancy, type II has a late infantile onset and is associated with survival into the second or third decade. Type III has its onset in childhood, and is slowly progressive. (J Med Genet 1996 Apr:33(4):281-3)Decompression, Surgical: A surgical operation for the relief of pressure in a body compartment or on a body part. (From Dorland, 28th ed)Paraparesis: Mild to moderate loss of bilateral lower extremity motor function, which may be a manifestation of SPINAL CORD DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; MUSCULAR DISEASES; INTRACRANIAL HYPERTENSION; parasagittal brain lesions; and other conditions.Animals, Newborn: Refers to animals in the period of time just after birth.Spinal Fractures: Broken bones in the vertebral column.Wheelchairs: Chairs mounted on wheels and designed to be propelled by the occupant.Glial Fibrillary Acidic Protein: An intermediate filament protein found only in glial cells or cells of glial origin. MW 51,000.Cord Blood Stem Cell Transplantation: Transplantation of STEM CELLS collected from the fetal blood remaining in the UMBILICAL CORD and the PLACENTA after delivery. Included are the HEMATOPOIETIC STEM CELLS.Amyotrophic Lateral Sclerosis: A degenerative disorder affecting upper MOTOR NEURONS in the brain and lower motor neurons in the brain stem and SPINAL CORD. Disease onset is usually after the age of 50 and the process is usually fatal within 3 to 6 years. Clinical manifestations include progressive weakness, atrophy, FASCICULATION, hyperreflexia, DYSARTHRIA, dysphagia, and eventual paralysis of respiratory function. Pathologic features include the replacement of motor neurons with fibrous ASTROCYTES and atrophy of anterior SPINAL NERVE ROOTS and corticospinal tracts. (From Adams et al., Principles of Neurology, 6th ed, pp1089-94)Astrocytes: A class of large neuroglial (macroglial) cells in the central nervous system - the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from "star" cells) are irregularly shaped with many long processes, including those with "end feet" which form the glial (limiting) membrane and directly and indirectly contribute to the BLOOD-BRAIN BARRIER. They regulate the extracellular ionic and chemical environment, and "reactive astrocytes" (along with MICROGLIA) respond to injury.Pain Threshold: Amount of stimulation required before the sensation of pain is experienced.Analgesics: Compounds capable of relieving pain without the loss of CONSCIOUSNESS.Nerve Tissue ProteinsEvoked Potentials: Electrical responses recorded from nerve, muscle, SENSORY RECEPTOR, or area of the CENTRAL NERVOUS SYSTEM following stimulation. They range from less than a microvolt to several microvolts. The evoked potential can be auditory (EVOKED POTENTIALS, AUDITORY), somatosensory (EVOKED POTENTIALS, SOMATOSENSORY), visual (EVOKED POTENTIALS, VISUAL), or motor (EVOKED POTENTIALS, MOTOR), or other modalities that have been reported.Substance P: An eleven-amino acid neurotransmitter that appears in both the central and peripheral nervous systems. It is involved in transmission of PAIN, causes rapid contractions of the gastrointestinal smooth muscle, and modulates inflammatory and immune responses.Spinal Cord Vascular Diseases: Pathological processes involving any of the BLOOD VESSELS feeding the SPINAL CORD, such as the anterior and paired posterior spinal arteries or their many branches. Disease processes may include ATHEROSCLEROSIS; EMBOLISM; and ARTERIOVENOUS MALFORMATIONS leading to ISCHEMIA or HEMORRHAGE into the spinal cord (hematomyelia).Neural Pathways: Neural tracts connecting one part of the nervous system with another.Peripheral Nerves: The nerves outside of the brain and spinal cord, including the autonomic, cranial, and spinal nerves. Peripheral nerves contain non-neuronal cells and connective tissue as well as axons. The connective tissue layers include, from the outside to the inside, the epineurium, the perineurium, and the endoneurium.Synaptic Transmission: The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.Trigeminal Nucleus, Spinal: Nucleus of the spinal tract of the trigeminal nerve. It is divided cytoarchitectonically into three parts: oralis, caudalis (TRIGEMINAL CAUDAL NUCLEUS), and interpolaris.Behavior, Animal: The observable response an animal makes to any situation.Neuronal Plasticity: The capacity of the NERVOUS SYSTEM to change its reactivity as the result of successive activations.Decerebrate State: A condition characterized by abnormal posturing of the limbs that is associated with injury to the brainstem. This may occur as a clinical manifestation or induced experimentally in animals. The extensor reflexes are exaggerated leading to rigid extension of the limbs accompanied by hyperreflexia and opisthotonus. This condition is usually caused by lesions which occur in the region of the brainstem that lies between the red nuclei and the vestibular nuclei. In contrast, decorticate rigidity is characterized by flexion of the elbows and wrists with extension of the legs and feet. The causative lesion for this condition is located above the red nuclei and usually consists of diffuse cerebral damage. (From Adams et al., Principles of Neurology, 6th ed, p358)Rats, Wistar: A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.Microglia: The third type of glial cell, along with astrocytes and oligodendrocytes (which together form the macroglia). Microglia vary in appearance depending on developmental stage, functional state, and anatomical location; subtype terms include ramified, perivascular, ameboid, resting, and activated. Microglia clearly are capable of phagocytosis and play an important role in a wide spectrum of neuropathologies. They have also been suggested to act in several other roles including in secretion (e.g., of cytokines and neural growth factors), in immunological processing (e.g., antigen presentation), and in central nervous system development and remodeling.Infarction: Formation of an infarct, which is NECROSIS in tissue due to local ISCHEMIA resulting from obstruction of BLOOD CIRCULATION, most commonly by a THROMBUS or EMBOLUS.Brain: The part of CENTRAL NERVOUS SYSTEM that is contained within the skull (CRANIUM). Arising from the NEURAL TUBE, the embryonic brain is comprised of three major parts including PROSENCEPHALON (the forebrain); MESENCEPHALON (the midbrain); and RHOMBENCEPHALON (the hindbrain). The developed brain consists of CEREBRUM; CEREBELLUM; and other structures in the BRAIN STEM.Action Potentials: Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.Chick Embryo: The developmental entity of a fertilized chicken egg (ZYGOTE). The developmental process begins about 24 h before the egg is laid at the BLASTODISC, a small whitish spot on the surface of the EGG YOLK. After 21 days of incubation, the embryo is fully developed before hatching.Dura Mater: The outermost of the three MENINGES, a fibrous membrane of connective tissue that covers the brain and the spinal cord.Chondroitin ABC Lyase: An enzyme that catalyzes the eliminative degradation of polysaccharides containing 1,4-beta-D-hexosaminyl and 1,3-beta-D-glucuronosyl or 1,3-alpha-L-iduronosyl linkages to disaccharides containing 4-deoxy-beta-D-gluc-4-enuronosyl groups. (Enzyme Nomenclature, 1992)Forelimb: A front limb of a quadruped. (The Random House College Dictionary, 1980)Substantia Gelatinosa: Gelatinous-appearing material in the dorsal horn of the spinal cord, consisting chiefly of Golgi type II neurons and some larger nerve cells.Subarachnoid Space: The space between the arachnoid membrane and PIA MATER, filled with CEREBROSPINAL FLUID. It contains large blood vessels that supply the BRAIN and SPINAL CORD.Peripheral Nerve Injuries: Injuries to the PERIPHERAL NERVES.Sacrum: Five fused VERTEBRAE forming a triangle-shaped structure at the back of the PELVIS. It articulates superiorly with the LUMBAR VERTEBRAE, inferiorly with the COCCYX, and anteriorly with the ILIUM of the PELVIS. The sacrum strengthens and stabilizes the PELVIS.Demyelinating Diseases: Diseases characterized by loss or dysfunction of myelin in the central or peripheral nervous system.Neural Conduction: The propagation of the NERVE IMPULSE along the nerve away from the site of an excitation stimulus.Meninges: The three membranes that cover the BRAIN and the SPINAL CORD. They are the dura mater, the arachnoid, and the pia mater.Pressure Ulcer: An ulceration caused by prolonged pressure on the SKIN and TISSUES when one stays in one position for a long period of time, such as lying in bed. The bony areas of the body are the most frequently affected sites which become ischemic (ISCHEMIA) under sustained and constant pressure.Morphine: The principal alkaloid in opium and the prototype opiate analgesic and narcotic. Morphine has widespread effects in the central nervous system and on smooth muscle.Neurologic Examination: Assessment of sensory and motor responses and reflexes that is used to determine impairment of the nervous system.Spinal Osteophytosis: Outgrowth of immature bony processes or bone spurs (OSTEOPHYTE) from the VERTEBRAE, reflecting the presence of degenerative disease and calcification. It commonly occurs in cervical and lumbar SPONDYLOSIS.Evoked Potentials, Motor: The electrical response evoked in a muscle or motor nerve by electrical or magnetic stimulation. Common methods of stimulation are by transcranial electrical and TRANSCRANIAL MAGNETIC STIMULATION. It is often used for monitoring during neurosurgery.Nerve Fibers: Slender processes of NEURONS, including the AXONS and their glial envelopes (MYELIN SHEATH). Nerve fibers conduct nerve impulses to and from the CENTRAL NERVOUS SYSTEM.Treatment Outcome: Evaluation undertaken to assess the results or consequences of management and procedures used in combating disease in order to determine the efficacy, effectiveness, safety, and practicability of these interventions in individual cases or series.Rhizotomy: Surgical interruption of a spinal or cranial nerve root. (From Dorland, 28th ed)H-Reflex: A monosynaptic reflex elicited by stimulating a nerve, particularly the tibial nerve, with an electric shock.Medulla Oblongata: The lower portion of the BRAIN STEM. It is inferior to the PONS and anterior to the CEREBELLUM. Medulla oblongata serves as a relay station between the brain and the spinal cord, and contains centers for regulating respiratory, vasomotor, cardiac, and reflex activities.Electrophysiology: The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.Nerve Fibers, Myelinated: A class of nerve fibers as defined by their structure, specifically the nerve sheath arrangement. The AXONS of the myelinated nerve fibers are completely encased in a MYELIN SHEATH. They are fibers of relatively large and varied diameters. Their NEURAL CONDUCTION rates are faster than those of the unmyelinated nerve fibers (NERVE FIBERS, UNMYELINATED). Myelinated nerve fibers are present in somatic and autonomic nerves.Glycine Agents: Substances used for their pharmacological actions on glycinergic systems. Glycinergic agents include agonists, antagonists, degradation or uptake inhibitors, depleters, precursors, and modulators of receptor function.Muscle, Skeletal: A subtype of striated muscle, attached by TENDONS to the SKELETON. Skeletal muscles are innervated and their movement can be consciously controlled. They are also called voluntary muscles.Scoliosis: An appreciable lateral deviation in the normally straight vertical line of the spine. (Dorland, 27th ed)Spinal Puncture: Tapping fluid from the subarachnoid space in the lumbar region, usually between the third and fourth lumbar vertebrae.Hyperesthesia: Increased sensitivity to cutaneous stimulation due to a diminished threshold or an increased response to stimuli.Synapses: Specialized junctions at which a neuron communicates with a target cell. At classical synapses, a neuron's presynaptic terminal releases a chemical transmitter stored in synaptic vesicles which diffuses across a narrow synaptic cleft and activates receptors on the postsynaptic membrane of the target cell. The target may be a dendrite, cell body, or axon of another neuron, or a specialized region of a muscle or secretory cell. Neurons may also communicate via direct electrical coupling with ELECTRICAL SYNAPSES. Several other non-synaptic chemical or electric signal transmitting processes occur via extracellular mediated interactions.Mice, Inbred C57BLSacrococcygeal Region: The body region between (and flanking) the SACRUM and COCCYX.Stilbamidines: STILBENES with AMIDINES attached.Urinary Bladder: A musculomembranous sac along the URINARY TRACT. URINE flows from the KIDNEYS into the bladder via the ureters (URETER), and is held there until URINATION.Reflex, Abnormal: An abnormal response to a stimulus applied to the sensory components of the nervous system. This may take the form of increased, decreased, or absent reflexes.In Situ Hybridization: A technique that localizes specific nucleic acid sequences within intact chromosomes, eukaryotic cells, or bacterial cells through the use of specific nucleic acid-labeled probes.Analysis of Variance: A statistical technique that isolates and assesses the contributions of categorical independent variables to variation in the mean of a continuous dependent variable.Sensation: The process in which specialized SENSORY RECEPTOR CELLS transduce peripheral stimuli (physical or chemical) into NERVE IMPULSES which are then transmitted to the various sensory centers in the CENTRAL NERVOUS SYSTEM.Spinal Dysraphism: Congenital defects of closure of one or more vertebral arches, which may be associated with malformations of the spinal cord, nerve roots, congenital fibrous bands, lipomas, and congenital cysts. These malformations range from mild (e.g., SPINA BIFIDA OCCULTA) to severe, including rachischisis where there is complete failure of neural tube and spinal cord fusion, resulting in exposure of the spinal cord at the surface. Spinal dysraphism includes all forms of spina bifida. The open form is called SPINA BIFIDA CYSTICA and the closed form is SPINA BIFIDA OCCULTA. (From Joynt, Clinical Neurology, 1992, Ch55, p34)Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Mice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.N-Methylaspartate: An amino acid that, as the D-isomer, is the defining agonist for the NMDA receptor subtype of glutamate receptors (RECEPTORS, NMDA).Neuroprotective Agents: Drugs intended to prevent damage to the brain or spinal cord from ischemia, stroke, convulsions, or trauma. Some must be administered before the event, but others may be effective for some time after. They act by a variety of mechanisms, but often directly or indirectly minimize the damage produced by endogenous excitatory amino acids.Movement: The act, process, or result of passing from one place or position to another. It differs from LOCOMOTION in that locomotion is restricted to the passing of the whole body from one place to another, while movement encompasses both locomotion but also a change of the position of the whole body or any of its parts. Movement may be used with reference to humans, vertebrate and invertebrate animals, and microorganisms. Differentiate also from MOTOR ACTIVITY, movement associated with behavior.Tibial Nerve: The medial terminal branch of the sciatic nerve. The tibial nerve fibers originate in lumbar and sacral spinal segments (L4 to S2). They supply motor and sensory innervation to parts of the calf and foot.Nerve Degeneration: Loss of functional activity and trophic degeneration of nerve axons and their terminal arborizations following the destruction of their cells of origin or interruption of their continuity with these cells. The pathology is characteristic of neurodegenerative diseases. Often the process of nerve degeneration is studied in research on neuroanatomical localization and correlation of the neurophysiology of neural pathways.Electrodes, Implanted: Surgically placed electric conductors through which ELECTRIC STIMULATION is delivered to or electrical activity is recorded from a specific point inside the body.Reticular Formation: A region extending from the PONS & MEDULLA OBLONGATA through the MESENCEPHALON, characterized by a diversity of neurons of various sizes and shapes, arranged in different aggregations and enmeshed in a complicated fiber network.gamma-Aminobutyric Acid: The most common inhibitory neurotransmitter in the central nervous system.Gliosis: The production of a dense fibrous network of neuroglia; includes astrocytosis, which is a proliferation of astrocytes in the area of a degenerative lesion.Nociception: Sensing of noxious mechanical, thermal or chemical stimuli by NOCICEPTORS. It is the sensory component of visceral and tissue pain (NOCICEPTIVE PAIN).Nerve Fibers, Unmyelinated: A class of nerve fibers as defined by their nerve sheath arrangement. The AXONS of the unmyelinated nerve fibers are small in diameter and usually several are surrounded by a single MYELIN SHEATH. They conduct low-velocity impulses, and represent the majority of peripheral sensory and autonomic fibers, but are also found in the BRAIN and SPINAL CORD.Receptors, Neurokinin-1: A class of cell surface receptors for TACHYKININS with a preference for SUBSTANCE P. Neurokinin-1 (NK-1) receptors have been cloned and are members of the G protein coupled receptor superfamily. They are found on many cell types including central and peripheral neurons, smooth muscle cells, acinar cells, endothelial cells, fibroblasts, and immune cells.Manipulation, Spinal: Adjustment and manipulation of the vertebral column.Sensory Receptor Cells: Specialized afferent neurons capable of transducing sensory stimuli into NERVE IMPULSES to be transmitted to the CENTRAL NERVOUS SYSTEM. Sometimes sensory receptors for external stimuli are called exteroceptors; for internal stimuli are called interoceptors and proprioceptors.Ependyma: A thin membrane that lines the CEREBRAL VENTRICLES and the central canal of the SPINAL CORD.Reflex, Monosynaptic: A reflex in which the AFFERENT NEURONS synapse directly on the EFFERENT NEURONS, without any INTERCALATED NEURONS. (Lockard, Desk Reference for Neuroscience, 2nd ed.)Phrenic Nerve: The motor nerve of the diaphragm. The phrenic nerve fibers originate in the cervical spinal column (mostly C4) and travel through the cervical plexus to the diaphragm.Urination: Discharge of URINE, liquid waste processed by the KIDNEY, from the body.Periodicity: The tendency of a phenomenon to recur at regular intervals; in biological systems, the recurrence of certain activities (including hormonal, cellular, neural) may be annual, seasonal, monthly, daily, or more frequently (ultradian).Dose-Response Relationship, Drug: The relationship between the dose of an administered drug and the response of the organism to the drug.Gait Disorders, Neurologic: Gait abnormalities that are a manifestation of nervous system dysfunction. These conditions may be caused by a wide variety of disorders which affect motor control, sensory feedback, and muscle strength including: CENTRAL NERVOUS SYSTEM DISEASES; PERIPHERAL NERVOUS SYSTEM DISEASES; NEUROMUSCULAR DISEASES; or MUSCULAR DISEASES.Red Nucleus: A pinkish-yellow portion of the midbrain situated in the rostral mesencephalic tegmentum. It receives a large projection from the contralateral half of the CEREBELLUM via the superior cerebellar peduncle and a projection from the ipsilateral MOTOR CORTEX.Gene Expression Regulation, Developmental: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action during the developmental stages of an organism.Serotonin: A biochemical messenger and regulator, synthesized from the essential amino acid L-TRYPTOPHAN. In humans it is found primarily in the central nervous system, gastrointestinal tract, and blood platelets. Serotonin mediates several important physiological functions including neurotransmission, gastrointestinal motility, hemostasis, and cardiovascular integrity. Multiple receptor families (RECEPTORS, SEROTONIN) explain the broad physiological actions and distribution of this biochemical mediator.Neural Inhibition: The function of opposing or restraining the excitation of neurons or their target excitable cells.Encephalomyelitis, Autoimmune, Experimental: An experimental animal model for central nervous system demyelinating disease. Inoculation with a white matter emulsion combined with FREUND'S ADJUVANT, myelin basic protein, or purified central myelin triggers a T cell-mediated immune response directed towards central myelin. The pathologic features are similar to MULTIPLE SCLEROSIS, including perivascular and periventricular foci of inflammation and demyelination. Subpial demyelination underlying meningeal infiltrations also occurs, which is also a feature of ENCEPHALOMYELITIS, ACUTE DISSEMINATED. Passive immunization with T-cells from an afflicted animal to a normal animal also induces this condition. (From Immunol Res 1998;17(1-2):217-27; Raine CS, Textbook of Neuropathology, 2nd ed, p604-5)Multiple Sclerosis: An autoimmune disorder mainly affecting young adults and characterized by destruction of myelin in the central nervous system. Pathologic findings include multiple sharply demarcated areas of demyelination throughout the white matter of the central nervous system. Clinical manifestations include visual loss, extra-ocular movement disorders, paresthesias, loss of sensation, weakness, dysarthria, spasticity, ataxia, and bladder dysfunction. The usual pattern is one of recurrent attacks followed by partial recovery (see MULTIPLE SCLEROSIS, RELAPSING-REMITTING), but acute fulminating and chronic progressive forms (see MULTIPLE SCLEROSIS, CHRONIC PROGRESSIVE) also occur. (Adams et al., Principles of Neurology, 6th ed, p903)Capsaicin: An alkylamide found in CAPSICUM that acts at TRPV CATION CHANNELS.Pain, Intractable: Persistent pain that is refractory to some or all forms of treatment.Stem Cells: Relatively undifferentiated cells that retain the ability to divide and proliferate throughout postnatal life to provide progenitor cells that can differentiate into specialized cells.Naloxone: A specific opiate antagonist that has no agonist activity. It is a competitive antagonist at mu, delta, and kappa opioid receptors.Cord Factors: Toxic glycolipids composed of trehalose dimycolate derivatives. They are produced by MYCOBACTERIUM TUBERCULOSIS and other species of MYCOBACTERIUM. They induce cellular dysfunction in animals.Nervous System: The entire nerve apparatus, composed of a central part, the brain and spinal cord, and a peripheral part, the cranial and spinal nerves, autonomic ganglia, and plexuses. (Stedman, 26th ed)Neuronal Tract-Tracers: Substances used to identify the location and to characterize the types of NEURAL PATHWAYS.Nerve Tissue: Differentiated tissue of the central nervous system composed of NERVE CELLS, fibers, DENDRITES, and specialized supporting cells.Glycine: A non-essential amino acid. It is found primarily in gelatin and silk fibroin and used therapeutically as a nutrient. It is also a fast inhibitory neurotransmitter.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.TailFunctional Laterality: Behavioral manifestations of cerebral dominance in which there is preferential use and superior functioning of either the left or the right side, as in the preferred use of the right hand or right foot.Neurosurgical Procedures: Surgery performed on the nervous system or its parts.Nerve Growth Factors: Factors which enhance the growth potentialities of sensory and sympathetic nerve cells.Myelin Proteins: MYELIN-specific proteins that play a structural or regulatory role in the genesis and maintenance of the lamellar MYELIN SHEATH structure.Spasm: An involuntary contraction of a muscle or group of muscles. Spasms may involve SKELETAL MUSCLE or SMOOTH MUSCLE.Brown-Sequard Syndrome: A syndrome associated with injury to the lateral half of the spinal cord. The condition is characterized by the following clinical features (which are found below the level of the lesion): contralateral hemisensory anesthesia to pain and temperature, ipsilateral loss of propioception, and ipsilateral motor paralysis. Tactile sensation is generally spared. (From Adams et al., Principles of Neurology, 6th ed, p162).Constriction: The act of constricting.Survival of Motor Neuron 1 Protein: A SMN complex protein that is essential for the function of the SMN protein complex. In humans the protein is encoded by a single gene found near the inversion telomere of a large inverted region of CHROMOSOME 5. Mutations in the gene coding for survival of motor neuron 1 protein may result in SPINAL MUSCULAR ATROPHIES OF CHILDHOOD.Motor Neuron Disease: Diseases characterized by a selective degeneration of the motor neurons of the spinal cord, brainstem, or motor cortex. Clinical subtypes are distinguished by the major site of degeneration. In AMYOTROPHIC LATERAL SCLEROSIS there is involvement of upper, lower, and brainstem motor neurons. In progressive muscular atrophy and related syndromes (see MUSCULAR ATROPHY, SPINAL) the motor neurons in the spinal cord are primarily affected. With progressive bulbar palsy (BULBAR PALSY, PROGRESSIVE), the initial degeneration occurs in the brainstem. In primary lateral sclerosis, the cortical neurons are affected in isolation. (Adams et al., Principles of Neurology, 6th ed, p1089)Cell Count: The number of CELLS of a specific kind, usually measured per unit volume or area of sample.

Adenoviral gene transfer into the normal and injured spinal cord: enhanced transgene stability by combined administration of temperature-sensitive virus and transient immune blockade. (1/10835)

This study characterized gene transfer into both normal and injured adult rat dorsal spinal cord using first (E1-/E3-) or second (E1-/E2A125/E3-, temperature-sensitive; ts) generation of replication-defective adenoviral (Ad) vectors. A novel immunosuppressive regimen aimed at blocking CD4/CD45 lymphocytic receptors was tested for improving transgene persistence. In addition, the effect of gene transfer on nociception was also evaluated. Seven days after treatment, numerous LacZ-positive cells were observed after transfection with either viral vector. By 21 days after transfection, beta-galactosidase staining was reduced and suggestive of ongoing cytopathology in both Ad-treated groups, despite the fact that the immunogenicity of LacZ/Adts appeared less when compared with that elicited by the LacZ/Ad vector. In contrast, immunosuppressed animals showed a significant (P < or = 0.05) increase in the number of LacZ-positive cells not displaying cytopathology. In these animals, a concomitant reduction in numbers of macrophages/microglia and CD4 and CD8 lymphocytes was observed. Only animals that received LacZ/Adts and immunosuppression showed transgene expression after 60 days. Similar results were observed in animals in which the L4-L5 dorsal roots were lesioned before transfection. Gene transfer into the dorsal spinal cord did not affect nociception, independent of the adenovirus vector. These results indicate that immune blockade of the CD4/CD45 lymphocytic receptors enhanced transgene stability in adult animals with normal or injured spinal cords and that persistent transgene expression in the spinal cord does not interfere with normal neural function.  (+info)

Activity-dependent metaplasticity of inhibitory and excitatory synaptic transmission in the lamprey spinal cord locomotor network. (2/10835)

Paired intracellular recordings have been used to examine the activity-dependent plasticity and neuromodulator-induced metaplasticity of synaptic inputs from identified inhibitory and excitatory interneurons in the lamprey spinal cord. Trains of spikes at 5-20 Hz were used to mimic the frequency of spiking that occurs in network interneurons during NMDA or brainstem-evoked locomotor activity. Inputs from inhibitory and excitatory interneurons exhibited similar activity-dependent changes, with synaptic depression developing during the spike train. The level of depression reached was greater with lower stimulation frequencies. Significant activity-dependent depression of inputs from excitatory interneurons and inhibitory crossed caudal interneurons, which are central elements in the patterning of network activity, usually developed between the fifth and tenth spikes in the train. Because these interneurons typically fire bursts of up to five spikes during locomotor activity, this activity-dependent plasticity will presumably not contribute to the patterning of network activity. However, in the presence of the neuromodulators substance P and 5-HT, significant activity-dependent metaplasticity of these inputs developed over the first five spikes in the train. Substance P induced significant activity-dependent depression of inhibitory but potentiation of excitatory interneuron inputs, whereas 5-HT induced significant activity-dependent potentiation of both inhibitory and excitatory interneuron inputs. Because these metaplastic effects are consistent with the substance P and 5-HT-induced modulation of the network output, activity-dependent metaplasticity could be a potential mechanism underlying the coordination and modulation of rhythmic network activity.  (+info)

Spinal cord-evoked potentials and muscle responses evoked by transcranial magnetic stimulation in 10 awake human subjects. (3/10835)

Transcranial magnetic stimulation (TCMS) causes leg muscle contractions, but the neural structures in the brain that are activated by TCMS and their relationship to these leg muscle responses are not clearly understood. To elucidate this, we concomitantly recorded leg muscle responses and thoracic spinal cord-evoked potentials (SCEPs) after TCMS for the first time in 10 awake, neurologically intact human subjects. In this report we provide evidence of direct and indirect activation of corticospinal neurons after TCMS. In three subjects, SCEP threshold (T) stimulus intensities recruited both the D wave (direct activation of corticospinal neurons) and the first I wave (I1, indirect activation of corticospinal neurons). In one subject, the D, I1, and I2 waves were recruited simultaneously, and in another subject, the I1 and I2 waves were recruited simultaneously. In the remaining five subjects, only the I1 wave was recruited first. More waves were recruited as the stimulus intensity increased. The presence of D and I waves in all subjects at low stimulus intensities verified that TCMS directly and indirectly activated corticospinal neurons supplying the lower extremities. Leg muscle responses were usually contingent on the SCEP containing at least four waves (D, I1, I2, and I3).  (+info)

Complete compensation in skilled reaching success with associated impairments in limb synergies, after dorsal column lesion in the rat. (4/10835)

Each of the dorsal columns of the rat spinal cord conveys primary sensory information, by way of the medullary dorsal column nucleus, to the ventrobasal thalamus on the contralateral side; thus the dorsal columns are an important source of neural input to the sensorimotor cortex. Damage to the dorsal columns causes impairments in synergistic proximal or whole-body movements in cats and distal limb impairments in primates, particularly in multiarticulated finger movements and tactile foviation while handling objects, but the behavioral effects of afferent fiber lesions in the dorsal columns of rodents have not been described. Female Long-Evans rats were trained to reach with a forelimb for food pellets and subsequently received lesions of the dorsomedial spinal cord at the C2 level, ipsilateral to their preferred limb. Reaching success completely recovered within a few days of dorsal column lesion. Nevertheless, a detailed analysis of high-speed video recordings revealed that rotatory limb movements (aiming, pronation, supination, etc.) were irreversibly impaired. Compensation was achieved with whole-body and alternate limb movements. These results indicate the following: (1) in the absence of the dorsal columns, other sensorimotor pathways support endpoint success in reaching; (2) sensory input conveyed by the dorsal columns is important for both proximal and distal limb movements used for skilled reaching; and (3) detailed behavioral analyses in addition to endpoint measures are necessary to completely describe the effects of dorsal column lesions.  (+info)

Neurite outgrowth-regulating properties of GABA and the effect of serum on mouse spinal cord neurons in culture. (5/10835)

Time-lapse photography was used to examine the effects of gamma-aminobutyric acid (GABA) on the outgrowth and motility of neurites in cultures from mouse spinal cord. GABA at concentrations of 100, 10 and 1 microM caused significant inhibition of neurite outgrowth and the motility of growth cones was significantly reduced by treatment with 100 and 10 microM GABA. This effect was mimicked by the GABA(B) receptor agonist baclofen, whereas the GABA(A) receptor agonist muscimol had no effect. The effect of GABA on outgrowth and motility seems to be dependent on the type of serum employed. The results reported here were obtained only when heat-inactivated serum was used and not when non heat-inactivated serum was added to the culture medium. They suggest that GABA has a role in the regulation of process outgrowth within the embryonic mouse spinal cord.  (+info)

Presence of the vesicular inhibitory amino acid transporter in GABAergic and glycinergic synaptic terminal boutons. (6/10835)

The characterization of the Caenorhabditis elegans unc-47 gene recently allowed the identification of a mammalian (gamma)-amino butyric acid (GABA) transporter, presumed to be located in the synaptic vesicle membrane. In situ hybridization data in rat brain suggested that it might also take up glycine and thus represent a general Vesicular Inhibitory Amino Acid Transporter (VIAAT). In the present study, we have investigated the localization of VIAAT in neurons by using a polyclonal antibody raised against the hydrophilic N-terminal domain of the protein. Light microscopy and immunocytochemistry in primary cultures or tissue sections of the rat spinal cord revealed that VIAAT was localized in a subset (63-65%) of synaptophysin-immunoreactive terminal boutons; among the VIAAT-positive terminals around motoneuronal somata, 32.9% of them were also immunoreactive for GAD65, a marker of GABAergic presynaptic endings. Labelling was also found apposed to clusters positive for the glycine receptor or for its associated protein gephyrin. At the ultrastructural level, VIAAT immunoreactivity was restricted to presynaptic boutons exhibiting classical inhibitory features and, within the boutons, concentrated over synaptic vesicle clusters. Pre-embedding detection of VIAAT followed by post-embedding detection of GABA or glycine on serial sections of the spinal cord or cerebellar cortex indicated that VIAAT was present in glycine-, GABA- or GABA- and glycine-containing boutons. Taken together, these data further support the view of a common vesicular transporter for these two inhibitory transmitters, which would be responsible for their costorage in the same synaptic vesicle and subsequent corelease at mixed GABA-and-glycine synapses.  (+info)

Cannabinoid suppression of noxious heat-evoked activity in wide dynamic range neurons in the lumbar dorsal horn of the rat. (7/10835)

The effects of cannabinoid agonists on noxious heat-evoked firing of 62 spinal wide dynamic range (WDR) neurons were examined in urethan-anesthetized rats (1 cell/animal). Noxious thermal stimulation was applied with a Peltier device to the receptive fields in the ipsilateral hindpaw of isolated WDR neurons. To assess the site of action, cannabinoids were administered systemically in intact and spinally transected rats and intraventricularly. Both the aminoalkylindole cannabinoid WIN55,212-2 (125 microg/kg iv) and the bicyclic cannabinoid CP55,940 (125 microg/kg iv) suppressed noxious heat-evoked activity. Responses evoked by mild pressure in nonnociceptive neurons were not altered by CP55,940 (125 microg/kg iv), consistent with previous observations with another cannabinoid agonist, WIN55,212-2. The cannabinoid induced-suppression of noxious heat-evoked activity was blocked by pretreatment with SR141716A (1 mg/kg iv), a competitive antagonist for central cannabinoid CB1 receptors. By contrast, intravenous administration of either vehicle or the receptor-inactive enantiomer WIN55,212-3 (125 microg/kg) failed to alter noxious heat-evoked activity. The suppression of noxious heat-evoked activity induced by WIN55,212-2 in the lumbar dorsal horn of intact animals was markedly attenuated in spinal rats. Moreover, intraventricular administration of WIN55,212-2 suppressed noxious heat-evoked activity in spinal WDR neurons. By contrast, both vehicle and enantiomer were inactive. These findings suggest that cannabinoids selectively modulate the activity of nociceptive neurons in the spinal dorsal horn by actions at CB1 receptors. This modulation represents a suppression of pain neurotransmission because the inhibitory effects are selective for pain-sensitive neurons and are observed with different modalities of noxious stimulation. The data also provide converging lines of evidence for a role for descending antinociceptive mechanisms in cannabinoid modulation of spinal nociceptive processing.  (+info)

Pharmacodynamic actions of (S)-2-[4,5-dihydro-5-propyl-2-(3H)-furylidene]-1,3-cyclopentanedione (oudenone). (8/10835)

The pharmacodynamic actions of (S)-2-[4,5-dihydro-5-propyl-2(3H)-furylidene]-1,3-cyclopentanedione (oudenone) were studied in both anesthetized animals and isolated organs. Oudenone (10--40 mg/kg i.v.) induced an initial rise in blood pressure followed by a prolonged hypotension in the anesthetized rats. In unanesthetized spontaneously hypertensive rats (SHR), oudenone (5--200 mg/kg p.o.) caused a dose-related decrease in the systolic blood pressure. The initial pressor effect was diminished by pretreatments with phentolamine, guanethidine, hexamethonium and was abolished in the pithed rats. In addition, intracisternal administrations of oudenone (100--600 mug/kg) showed a marked increase in blood pressure in the anesthetized rats, suggesting that the pressor effect may be due to centrally mediated actions. Oudenone, given intra-arterially into the femoral artery (400--800 mug/kg), caused a long-lasting vasodilation in anesthetized dogs. At a relatively high dose (40 mg/kg i.v.), oudenone antagonized all pressor responses to autonomic agents and central vagus nerve stimulation in anesthetized rats and dogs, however, oudenone showed no anti-cholinergic,-histaminergic, beta-adrenergic and adrenergic neuron blocking properties.  (+info)

  • In healthy people, some spinal cord neurons dampen pain signals, allowing individuals to tolerate intense stimuli at times, such as when a woman is giving birth or during a fight. (dana.org)
  • Normally, when a pain signal arrives from sensory nerves, it stimulates both relay neurons and inhibitory neurons in the spinal cord. (dana.org)
  • BDNF then binds to a protein on the surface of relay neurons in the spinal cord, which causes the chloride ion pump to stop working. (dana.org)
  • To investigate the functional consequences of the interplay between Shh signaling and calcium spike activity, a crucial biological outcome will be studied: dorsoventral differentiation of developing spinal neurons. (elsevier.com)
  • After a spinal cord injury there is an increased production of a protein (RhoA) that blocks regeneration of nerve cells that carry signals along the spinal cord and prevents the injured tissue from healing. (thefreedictionary.com)
  • It has been identified that patients who have received Medtronic spinal cord stimulation devices (see below for lists of devices affected by the hazard alert, including neurostimulators, leads, kits and programmers) have a very small risk of developing a tissue mass around a device lead that can cause spinal cord compression. (thefreedictionary.com)
  • Through low-voltage electrical stimulation, the normal pain signals which travel in the spinal cord are altered to provide partial or complete pain relief. (thefreedictionary.com)
  • We have developed a mathematical model representing cellular and molecular spread of ALS in the human spinal cord. (ucsb.edu)
  • Domain dimension and shape was obtained by reconstructing human spinal cord from high-resolution magnetic resonance (MR) images and known gross and histological neuroanatomy. (ucsb.edu)
  • When the neural tissue is injured or its function is imbalanced, as for patients suffering from spinal cord injury or epilepsy, recreating the remarkable plasticity of the developing nervous system towards repairing and regenerating damaged cells and connections is the ultimate goal. (elsevier.com)
  • Four weeks following SCI, FAA levels were markedly reduced in spinal cord tissue. (nih.gov)
  • The signal then passes through the spinal cord, where initial processing occurs, and travels to the brain, where it is perceived as pain. (dana.org)
  • The spinal cord is the continuation of the brain stem medulla below the foramen magnum. (lecturio.com)
  • This study will test the hypothesis that the Shh gradient across the dorsoventral axis of the nervous system contributes to establish a gradient of calcium-dependent electrical activity across the dorsoventral developing spinal cord that in turn regulates neuronal differentiation. (elsevier.com)
  • Our objective was to assess the relative merits of iTRAQ analysis of fresh frozen versus FFPE nervous tissues by comparing experimental autoimmune encephalomyelitis (EAE)-induced proteomic changes in FFPE rat spinal cords and frozen tissues. (figshare.com)
  • This investigation of mechanisms underlying neuronal differentiation may set the basis for devising treatments for neurological disorders such as pediatric epilepsy and spinal cord injury, in which both the reestablishment of balanced excitability and the reposition of damaged cells are key events for promoting recovery. (elsevier.com)
  • The spinal cord is a bundle of nerve fibers, no thicker than the human thumb, that links the brain with the rest of the body. (encyclopedia.com)
  • The nerve fibers enter the spinal cord through the dorsal root. (washington.edu)
  • We found a central role for so-called proprioceptive afferents, nerve fibers which signal proprioceptive information back to the spinal cord," says Takeoka. (eurekalert.org)
  • That leads to the rapid death of neurons, damage to the insulating sheaths around nerve fibers that allow them to send signals, and the formation of a scar that blocks the regeneration of the spinal cord's nerve cells. (eurekalert.org)
  • The researchers found certain nerve fibers that were not damaged when the spinal cord was injured spontaneously grew, or sprouted, and compensated for the severed connections, allowing the monkeys to gain back much sensation and movement. (livescience.com)
  • The corticospinal tract is a bundle of nerve fibers that connects the brain's cortex with the spinal cord. (livescience.com)
  • Although trauma, degenerative back disease, and genetic disorders can cause pressure on the spinal cord, the term spinal cord compression is usually reserved for cases in which the presence of a tumor results in pressure on the spinal cord. (encyclopedia.com)
  • The tumor may originate in a number of areas and either directly or indirectly put pressure on the cord. (encyclopedia.com)
  • In rare cases, children have inherited genes that increase the risk of a brain or spinal cord tumor. (webmd.com)
  • That means there's no standard age for children to be diagnosed with a brain or spinal cord tumor. (webmd.com)
  • If her doctor suspects a tumor, your child may undergo imaging tests like a CT scan or MRI to get a picture of her brain or spinal cord. (webmd.com)
  • The pathologies associated with spinal cord infarction are numerous and include neoplasm, spinal epidural or subdural abscess, granuloma, spinal epidural or subdural hematoma, extramedullary spinal tumor (including meningioma, neurofibroma, extradural lymphoma, metastasis), and herniated intervertebral disk. (medscape.com)
  • A spinal cord tumor may be either a cancerous or noncancerous lesion in the spinal cord that grows between the membranes covering the spinal cord or in the spinal canal. (faqs.org)
  • A tumor here can compress the spinal cord or its nerve roots,so even a noncancerous growth may be disabling unless it's properly treated. (faqs.org)
  • Treatment also may include pain relievers and drugs to lessen swelling around the tumor, and relieve pressure on the spinal cord. (faqs.org)
  • A risk factor is anything that increases your chances of getting a disease such as a brain or spinal cord tumor. (cancer.org)
  • An illustration shows an example of spinal cord compression caused by a tumor.Photo Source:123RF.com. (spineuniverse.com)
  • The first step in diagnosing a spinal cord tumor includes a discussion of the child's health history and a thorough physical examination. (spineuniverse.com)
  • If a spinal cord tumor is suspected, the child will need to undergo some diagnostic tests to rule out other possible health problems. (spineuniverse.com)
  • The microscopic appearance of the tumor after it is biopsied or excised (histopathology), is essential for determining the appropriate treatment of a spinal cord tumor. (spineuniverse.com)
  • Surgery is performed to remove or reduce the size of the tumor and alleviate the pressure ont he spinal column caused by the tumor. (spineuniverse.com)
  • The tumor can put pressure on the cord if this occurs, causing compression. (healthline.com)
  • Your doctor may prescribe other treatments, such as radiation therapy or chemotherapy, to shrink a tumor that's causing cord compression. (healthline.com)
  • UCSF is home to one of the largest centers for spinal tumor care in the U.S., treating more than 10,000 patients each year. (ucsfhealth.org)
  • Spinal Cord wants to encourage researchers that are still working to consider conducting Systematic Reviews or Narrative Reviews. (nature.com)
  • With all of their background knowledge on the effects of the gut microbiome, the researchers hypothesized that changes in the gut microbiome could affect spinal cord injury recovery. (medicalnewstoday.com)
  • Purdue researchers have now shown that the micelles themselves repair damaged axons, fibers that transmit electrical impulses in the spinal cord. (redorbit.com)
  • The researchers used the chamber to study how well micelles repaired damaged nerve cells by measuring the "compound action potential," or the ability of a spinal cord to transmit signals. (redorbit.com)
  • A team of researchers at the University of South Florida investigating the short and long-term effects of ischemic stroke in a rodent model has found that stroke can cause long-term damage to the blood-spinal cord barrier (BSCB), creating a "toxic environment" in the spinal cord that might leave stroke survivors susceptible to motor dysfunction and disease pathology. (medicalnewstoday.com)
  • The researchers, who evaluated the BSCB in test animals at seven and 30 days after stroke modeling, found that ischemic stroke damaged the gray and white matter in the cervical spinal cord on both sides of the spinal column, based on analysis of electron microscope images. (medicalnewstoday.com)
  • These stroke-related alterations in the cervical spinal cord indicate pervasive and long-lasting BSCB damage that would severely affect spinal cord function, wrote the researchers, adding that the widespread microvascular impairment in the gray and white matter of the cervical spinal cord aggravated motor neuron deterioration and had the potential to cause motor dysfunction. (medicalnewstoday.com)
  • But now, U-M researchers have designed nanoparticles that intercept immune cells on their way to the spinal cord, redirecting them away from the injury. (eurekalert.org)
  • We hope this book can demonstrate advances in spinal cord injury as well as give references to the researchers, students and other related people. (scirp.org)
  • A major part of the map of spinal cords of mice is released by researchers from Allen Institute for Brain Science in Fremont. (emaxhealth.com)
  • Researchers were working several months in creating a map, which is to describe spinal cord of mice. (emaxhealth.com)
  • Allen Institute researchers expect to completely finish spinal cord map early next year, and the map will cost about $2.3 million. (emaxhealth.com)
  • This growth was able to restore 60 percent of the original spinal cord connections, the researchers said. (livescience.com)
  • Spinal cord stimulating device created by researchers at the Mayo Clinic. (upi.com)
  • Another of the researchers Dr Ann Turnley said most people with spinal cord damage often suffered devastating effects and there was usually little chance they would ever regain much movement. (abc.net.au)
  • If there are several tumors in different areas of the spinal cord at the same time, it may cause symptoms in a variety of spots on the body. (faqs.org)
  • Symptoms of spinal tumors generally develop slowly and worsen over time. (spineuniverse.com)
  • Symptoms may include loss of muscle function, sensation, or autonomic function in the parts of the body served by the spinal cord below the level of the injury. (scirp.org)
  • This delayed presentation of symptoms is related to the degree of strain placed on the spinal cord over time. (smartdraw.com)
  • Generally, the higher up the level of the injury to the spinal cord, the more severe the symptoms. (hopkinsmedicine.org)
  • Newly-formed tumors that originate in the spinal cord are unusual, especiallyamong children and the elderly. (faqs.org)
  • Thus, depending on which angle the spinal cord is compressed from, a person could experience numbness versus a loss of the ability to control muscles (often seen as an odd limp), depending on which area is compressed. (encyclopedia.com)
  • The area of skin innervated by a specific spinal nerve is called a dermatome, and the group of muscles innervated by a single spinal nerve is called a myotome. (wikipedia.org)
  • In subacute combined degeneration of spinal cord, the "combined" refers to the fact that the dorsal columns and lateral corticospinal tracts are both affected, in contrast to tabes dorsalis which is selective for the dorsal columns. (wikipedia.org)
  • A spinal cord injury disrupts the signals. (medlineplus.gov)
  • The bottom graphs show data indicating damaged spinal cord tissue recovered its "action potential," or ability to transmit signals, after treatment with the micelles. (redorbit.com)
  • Following spinal cord injury, disrupted neuronal pathways can no longer provide sufficiently strong signals to the spinal networks below the injury, often leading to permanent and devastating motor impairment," explains prof. Aya Takeoka from NERF (NeuroElectronics Research Flanders), an interdisciplinary research center empowered by VIB, KU Leuven and imec. (eurekalert.org)
  • The spinal cord functions primarily in the transmission of neural signals between the brain and the rest of the body (motor and sensory information, traveling in opposite directions down the spinal cord). (newworldencyclopedia.org)
  • The spinal cord functions primarily in the transmission of nerve signals from the motor cortex to the body, and from the afferent fibers of the sensory neurons to the sensory cortex. (wikipedia.org)
  • While a partial or incomplete spinal cord injury means that the spinal cord transmits some information to move the limbs or provides some sensory information from the skin. (spine.org)
  • An "incomplete" spinal cord injury involves preservation of motor or sensory function below the level of injury in the spinal cord. (wikipedia.org)