Animals ; Mice ; Motor Neurons/physiology* ; Spinal Cord

In recent years, the study of autophagy in spinal cord injury (SCI) gradually becomes the hot spot. However, the function of autophagy in the injured spinal cord is still controversial. In order to further understand the role of autophagy after SCI, we summarized the activation of autophagy, autophagic cell death, the relationship between autophagy and apoptosis, the function of autophagy in promoting the molecular metabolism and the role of autophagy after spinal cord injury. We concluded that the role of autophagy after SCI is a double-edged sword. Upregulating the level of autophagy appropriately can promote damaged proteins metabolism and inhibit apoptosis. However, excessive activation of antophagy may induce autophagic cell dealth. So we consider that the proper regulation of autophagy will be a new target in the treatment of SCI.
Animals ; Apoptosis ; Autophagy ; physiology ; Humans ; Spinal Cord Injuries ; etiology ; pathology

This review systematically introduces the functional connections among cardiovascular centers from spinal cord to cortex, and the mechanisms underlying pressor or depressor response of these cardiovascular centers, including the pathways, transmitters and receptors involved. The pressor or depressor response of these cardiovascular centers is mainly mediated by RVLM-sympathetic vasoconstrictor nerve system.
Blood Pressure ; physiology ; Central Nervous System ; physiology ; Cerebral Cortex ; physiology ; Humans ; Hypothalamus ; physiology ; Medulla Oblongata ; physiology ; Spinal Cord ; physiology

Pain is a multi-dimensional emotional experience, and pain sensation and pain emotion are the two main components. As for pain, previous studies only focused on a certain link of the pain transmission pathway or a certain key brain region, and there is a lack of evidence that connectivity of brain regions is involved in pain or pain regulation in the overall state. The establishment of new experimental tools and techniques has brought light to the study of neural pathways of pain sensation and pain emotion. In this paper, the structure and functional basis of the neural pathways involved in the formation of pain sensation and the regulation of pain emotion in the nervous system above the spinal cord level, including thalamus, amygdala, midbrain periaqueductal gray (PAG), parabrachial nucleus (PB) and medial prefrontal cortex (mPFC), are reviewed in recent years, providing clues for the in-depth study of pain.
Humans ; Pain ; Neural Pathways/physiology* ; Periaqueductal Gray/physiology* ; Brain ; Spinal Cord/physiology* ; Magnetic Resonance Imaging

To understand how the nervous system develops from a small pool of progenitors during early embryonic development, it is fundamentally important to identify the diversity of neuronal subtypes, decode the origin of neuronal diversity, and uncover the principles governing neuronal specification across different regions. Recent single-cell analyses have systematically identified neuronal diversity at unprecedented scale and speed, leaving the deconstruction of spatiotemporal mechanisms for generating neuronal diversity an imperative and paramount challenge. In this review, we highlight three distinct strategies deployed by neural progenitors to produce diverse neuronal subtypes, including predetermined, stochastic, and cascade diversifying models, and elaborate how these strategies are implemented in distinct regions such as the neocortex, spinal cord, retina, and hypothalamus. Importantly, the identity of neural progenitors is defined by their spatial position and temporal patterning factors, and each type of progenitor cell gives rise to distinguishable cohorts of neuronal subtypes. Microenvironmental cues, spontaneous activity, and connectional pattern further reshape and diversify the fate of unspecialized neurons in particular regions. The illumination of how neuronal diversity is generated will pave the way for producing specific brain organoids to model human disease and desired neuronal subtypes for cell therapy, as well as understanding the organization of functional neural circuits and the evolution of the nervous system.
Humans ; Neural Stem Cells/physiology* ; Neurons/physiology* ; Brain ; Spinal Cord ; Embryonic Development ; Cell Differentiation/physiology*

OBJECTIVETo explore the recording method of the electrophysiological signals in corticospinal tract (CST) of adult rats by plugging microelectrodes and analyze the characteristics of these signals. These could provide some valuable and basic neural electrophysiological information for further research of recovering and refunctioning after spinal cord injury.

METHODSThe microelectrodes were plugged into the corticospinal tract at the T8 spinal section of Sprague-Dawley rats and the neuro-electrical signals were identified and recorded from CST by means of the Cerebus System. The characteristics of the recorded signals were described with the help of the Offline sorter and Neuroexplorer softwares, including the wavelength, amplitude, discharging frequency, the synchrony among the multi-discharging units from the same electrode and two different electrodes, analysis of interspike interval (ISI), etc.

RESULTSThe continuous and steady spontaneous electrophysiological signals were recorded from CST. Three or four types of discharging signals originated from different discharging units were collected with each electrode. The waveform of the signals appeared bidirectional. The wavelengths were 0.6 - 1.3 ms with wave amplitudes at a grade of hundred microvoltage and high signal-noise ratios. The LFB staining proved that the electrodes were accurately plugged into the corticospinal tract.

CONCLUSIONThe neuro-electrical signals at a grade of hundred microvoltage could be recorded stably from the corticospinal tract of rats by the Cerebus System with the microelectrodes, which provided valuable and basic neural electrophysiological information for further research on recovering and refunctioning after spinal cord injury (SCI) by analyzing the characteristics of electrophysiological signals.

Animals ; Electrodes, Implanted ; Electrophysiological Phenomena ; physiology ; Evoked Potentials, Motor ; physiology ; Male ; Microelectrodes ; Pyramidal Tracts ; physiology ; Rats ; Rats, Sprague-Dawley ; Spinal Cord ; physiology ; Spinal Cord Injuries ; physiopathology

Full evidence and obvious reasons made it possible to arrive at the conclusion that the nature of transmission upon cerebrospinal neurons is overwhelmingly mechanical, not only in the periphery- between various receptors and afferent nerve terminals, and between surrounding tissues and free nerve endings- but also in the cerebral cortex. When viewed from the standpoint of the everchanging patterns of natural mechanical stimuli, the neurons in the conscious cerebral cortex and the pain endings in an acute inflammatory locus have the same situation very much in common. It is quite likely that natural mechanical stimuli dominate over cerebrospinal nervous phenomena and physiologists have been watching the missing mechanism at work in every experiment upon afferent nerve terminals and cerebral cortex that they have done. The terms "psychic tension" and "central excitatory state" comparable to muscular tonus are of interest because they involve the use of mathematical techniques in psychology and neurophysiology. They are capable of becoming weak or strong, and they serve as an inner stimulus to give impetus to behavior. Unfortunately, however, it is an elusive inner stimulus, and it defies a lucid definition. But natural mechanical stimuli embody the psychic tension and the central excitatory state ultimately. It seems now that we just found a place where constant complaints against neurophysiology and physiological psychology are ventilated. We may conclude that natural mechanical stimuli are the leading direct stimuli to cerebrospinal neurons in the human body, and the plastic and developmental nervous phenomena and mental phenomena can be explained objectively by a familliar datum of mechanical energy and that we can reasonably expect the day of regarding material world and spiritual world in the monistic conception of matter-energy system.
Animals ; Anura ; Cerebral Cortex/*physiology ; Human ; In Vitro ; Motor Neurons/physiology ; Nerve Endings/physiology ; Receptors, Sensory/*physiology ; Spinal Cord/*physiology

Acupuncture analgesia is involved in various functions of the whole nervous system. The spinal cord is the first station for processing and translating the acupuncture analgesia; the brain stem is the relay station for systematization, differentiation and analysis, excitation, synthesis of acupuncture analgesic message, playing an important role in acupuncture analgesia; the thalamus functions complicated analysis and comprehensive regulation on various messeges with many kinds of neurohumoral factors involved and it is a coordinate center for strengthening and controlling acupuncture analgesia; the limbic system and its nuclear groups with many neurotransmitters involved, play coordinate action on acupuncture analgesia; the cerebral cortex is the high center and functions not only excitation and inhibition processes, but also is a center for complicated regulation and command, strengthening acupuncture analgesia and inhibiting the excess, so as to exerts interaction of dynamic balance.
Acupuncture Analgesia ; Brain Stem ; physiology ; Cerebral Cortex ; physiology ; Humans ; Limbic System ; physiology ; Pain ; physiopathology ; Spinal Cord ; physiology ; Thalamus ; physiology

The autonomic nervous system (ANS) integrates the function of the internal organs for the homeostasis against various external environmental changes. The efferent components of the ANS are regulated by sensory signals arising from the viscera as well as non-visceral organs. The central neural networks that integrate these sensory signals and modify visceral motor output are complex, and synaptic reflexes formed in the brainstem and spinal cord integrate behavioral responses and visceral responses through the central neural networks. A detailed understanding of the neural network presented above may explain the role of the vestibular system on the homeostasis more extensively.
Autonomic Nervous System ; Brain Stem ; Homeostasis ; Physiology ; Reflex ; Solitary Nucleus ; Spinal Cord ; Spinal Cord Lateral Horn ; Viscera

PURPOSE: To describe a technique for urodynamic diagnosis of detrusor sphincter dyssynergia (DSD) using urethral pressure measurements and examine potential associations between urethral pressure and bladder physiology among patients with DSD. METHODS: Multiple sclerosis (MS) and spinal cord injured (SCI) patients with known DSD diagnosed on videourodynamics (via electromyography or voiding cystourethrography) were retrospectively identified. Data from SCI and MS patients with detrusor overactivity (DO) without DSD were abstracted as control group. Urodynamics tracings were reviewed and urethral pressure DSD was defined based on comparison of DSD and control groups. RESULTS: Seventy-two patients with DSD were identified. Sixty-two (86%) had >20 cm H₂O urethral pressure amplitude during detrusor contraction. By comparison, 5 of 23 (22%) of control group had amplitude of >20 cm H₂O during episode of DO. Mean duration of urethral pressure DSD episode was 66 seconds (range, 10–500 seconds) and mean urethral pressure amplitude was 73 cm H₂O (range, 1–256 cm H₂O). Longer (>30 seconds) DSD episodes were significantly associated with male sex (81% vs. 50%, P=0.013) and higher bladder capacity (389 mL vs. 219 mL, P=0.0004). Urethral pressure amplitude measurements during DSD were not associated with significant urodynamic variables or neurologic pathology. CONCLUSIONS: Urethral pressure amplitude of >20 cm H2O during detrusor contraction occurred in 86% of patients with known DSD. Longer DSD episodes were associated with larger bladder capacity. Further studies exploring the relationship between urethral pressure measurements and bladder physiology could phenotype DSD as a measurable variable rather than a categorical observation.
Ataxia* ; Diagnosis* ; Electromyography ; Humans ; Male ; Multiple Sclerosis ; Pathology ; Phenotype ; Physiology ; Retrospective Studies ; Spinal Cord ; Spinal Cord Injuries ; Urinary Bladder ; Urodynamics*