scholarly journals State-Dependent Changes in Glutamate, Glycine, GABA, and Dopamine Levels in Cat Lumbar Spinal Cord

2008 ◽  
Vol 100 (2) ◽  
pp. 598-608 ◽  
Author(s):  
N. Taepavarapruk ◽  
P. Taepavarapruk ◽  
J. John ◽  
Y. Y. Lai ◽  
J. M. Siegel ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Receptor Antagonist ◽  
Rem Sleep ◽  
High Performance ◽  
Glycine Receptor ◽  
Lumbar Spinal Cord ◽  
Neuron Activity ◽  
Neural Pathways ◽  
Spinal Interneurons

Recent studies have indicated that the glycine receptor antagonist strychnine and the γ-aminobutyric acid type A (GABAA) receptor antagonist bicuculline reduced the rapid-eye-movement (REM) sleep-specific inhibition of sensory inflow via the dorsal spinocerebellar tract (DSCT). These findings imply that the spinal release of glycine and GABA may be due directly to the REM sleep-specific activation of reticulospinal neurons and/or glutamate-activated last-order spinal interneurons. This study used in vivo microdialysis and high-performance liquid chromatography analysis techniques to provide evidence for these possibilities. Microdialysis probes were stereotaxically positioned in the L3 spinal cord gray matter corresponding to sites where maximal cerebellar-evoked field potentials or individual DSCT and nearby spinoreticular tract (SRT) neurons could be recorded. Glutamate, glycine, and GABA levels significantly increased during REM sleep by approximately 48, 48, and 14%, respectively, compared with the control state of wakefulness. In contrast, dopamine levels significantly decreased by about 28% during REM sleep compared with wakefulness. During the state of wakefulness, electrical stimulation of the nucleus reticularis gigantocellularis (NRGc) at intensities sufficient to inhibit DSCT neuron activity, also significantly increased glutamate and glycine levels by about 69 and 45%, respectively, but not GABA or dopamine levels. We suggest that the reciprocal changes in the release of glutamate, glycine, and GABA versus dopamine during REM sleep contribute to the reduction of sensory inflow to higher brain centers via the DSCT and nearby SRT during this behavioral state. The neural pathways involved in this process likely include reticulo- and diencephalospinal and spinal interneurons.

scholarly journals ASIC3-dependent spinal cord nociceptive signaling in cutaneous pain induced by lysophosphatidyl-choline

2020 ◽  
Author(s):  
Ludivine Pidoux ◽  
Kevin Delanoe ◽  
Eric Lingueglia ◽  
Emmanuel Deval
Keyword(s):  
Spinal Cord ◽  
Neuron Activity ◽  
Dorsal Spinal Cord ◽  
Spinal Cord Neurons ◽  
Lysophosphatidyl Choline ◽  
Nociceptive Pathway ◽  
Nociceptive Fibers ◽  
Cord Neuron ◽  
Peripheral Sensory

ABSTRACTLysophosphatidyl-choline (LPC), a member of the phospholipid family, has recently emerged as an interesting new player in pain. It has been proposed to mediate pain through Acid-Sensing Ion Channel 3 (ASIC3), a pain-related channel mainly expressed in peripheral sensory neurons. LPC potentiates ASIC3 current evoked by mild acidifications, but can also activate the channel at physiological pH, and its local injection in rodents evokes ASIC3-dependent pain. We combine here in vivo recordings of spinal cord neuron activity with subcutaneous LPC injection to analyze the mechanism of action associated with the LPC-induced, ASIC3-dependent pain in peripheral and spinal cord neurons. We show that a single cutaneous injection of LPC exclusively affects the nociceptive pathway. It evokes an ASIC3-dependent short-term sensitization of nociceptive fibers that drives hyperexcitability of projecting neurons within the dorsal spinal cord without apparent central sensitization.

Antagonism of the Antinocifensive Action of Halothane by Intrathecal Administration of GABA-A Receptor Antagonists

1996 ◽  
Vol 84 (5) ◽  
pp. 1205-1214 ◽  
Author(s):  
Peggy Mason ◽  
Casey A. Owens ◽  
Donna L. Hammond
Keyword(s):  
Spinal Cord ◽  
Receptor Antagonist ◽  
Gabaa Receptor ◽  
Glycine Receptor ◽  
Intrathecal Administration ◽  
Aminobutyric Acid ◽  
Gamma Aminobutyric Acid ◽  
Receptor Antagonists ◽  
Response Latencies ◽  
Halothane Concentration

Background The hind brain and the spinal cord, regions that contain high concentrations of gamma-aminobutyric acid (GABA) and GABA receptors, have been implicated as sites of action of inhalational anesthetics. Previous studies have established that general anesthetics potentiate the effects of gamma-aminobutyric acid at the GABAA receptor. It was therefore hypothesized that the suppression of nocifensive movements during anesthesia is due to an enhancement of GABAA receptor-mediated transmission within the spinal cord. Methods Rats in which an intrathecal catheter had been implanted 1 week earlier were anesthetized with halothane. Core temperature was maintained at a steady level. After MAC determination, the concentration of halothane was adjusted to that at which the rats last moved in response to tail clamping. Saline, a GABAA, a GABAB, or glycine receptor antagonist was then injected intrathecally. The latency to move in response to application of the tail clamp was redetermined 5 min later, after which the halothane concentration was increased by 0.2%. Response latencies to application of the noxious stimulus were measured at 7-min intervals during the subsequent 35 min. To determine whether these antagonists altered baseline response latencies by themselves, another experiment was conducted in which the concentration of halothane was not increased after intrathecal administration of GABAA receptor antagonists. Results Intrathecal administration of the GABAA receptor antagonists bicuculline (0.3 micrograms) or picrotoxin (0.3, 1.0 micrograms) antagonized the suppression of nocifensive movement produced by the small increase in halothane concentration. In contrast, the antinocifensive effect of the increase in halothane concentration was not attenuated by the GABAB receptor antagonist CGP 35348 or the glycine receptor antagonist strychnine. By themselves, the GABAA receptor antagonists did not alter response latency in rats anesthetized with sub-MAC concentrations of halothane. Conclusions Intrathecal administration of bicuculline or picrotoxin, at doses that do not change the latency to pinch-evoked movement when administered alone, antagonized the suppression of noxious-evoked movement produced by halothane concentrations equal to or greater than MAC. These results suggest that enhancement of GABAA receptor-mediated transmission within the spinal cord contributes to halothane's ability to suppress nocifensive movements.

The neuroprotective activity of the glycine receptor antagonist GV150526: an in vivo study by magnetic resonance imaging

2001 ◽  
Vol 419 (2-3) ◽  
pp. 147-153 ◽  
Author(s):  
Angelo Reggiani ◽  
Claudio Pietra ◽  
Roberto Arban ◽  
Pasquina Marzola ◽  
Uliano Guerrini ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Receptor Antagonist ◽  
Glycine Receptor ◽  
In Vivo Study ◽  
Neuroprotective Activity ◽  
Resonance Imaging

Active Dendritic Integration of Inhibitory Synaptic Inputs In Vivo

2003 ◽  
Vol 90 (6) ◽  
pp. 3617-3624 ◽  
Author(s):  
Jason J. Kuo ◽  
Robert H. Lee ◽  
Michael D. Johnson ◽  
Heather M. Heckman ◽  
C. J. Heckman
Keyword(s):  
Spinal Cord ◽  
Lumbar Spinal Cord ◽  
Standard State ◽  
Dendritic Integration ◽  
Local Inhibition ◽  
Highly Active ◽  
Linear Integration ◽  
Inward Currents ◽  
Lumbar Spinal

Synaptic integration in vivo often involves activation of many afferent inputs whose firing patterns modulate over time. In spinal motoneurons, sustained excitatory inputs undergo enormous enhancement due to persistent inward currents (PICs) that are generated primarily in the dendrites and are dependent on monoaminergic neuromodulatory input from the brain stem to the spinal cord. We measured the interaction between dendritic PICs and inhibition generated by tonic electrical stimulation of nerves to antagonist muscles during voltage clamp in motoneurons in the lumbar spinal cord of the cat. Separate samples of cells were obtained for two different states of monoaminergic input: standard (provided by the decerebrate preparation, which has tonic activity in monoaminergic axons) and minimal (the chloralose anesthetized preparation, which lacks tonic monoaminergic input). In the standard state, steady inhibition that increased the input conductance of the motoneurons by an average of 38% reduced the PIC by 69%. The range of this reduction, from <10% to >100%, was proportional to the magnitude of the applied inhibition. Thus nearly linear integration of synaptic inhibition may occur in these highly active dendrites. In the minimal state, PICs were much smaller, being approximately equal to inhibition-suppressed PICs in the standard state. Inhibition did not further reduce these already small PICs. Overall, these results demonstrate that inhibition from local spinal circuits can oppose the facilitation of dendritic PICs by descending monoaminergic inputs. As a result, local inhibition may also suppress active dendritic integration of excitatory inputs.

Production of the nmda/glycine receptor antagonist 7-chlorokynurenic acid in vivo

1995 ◽  
Vol 15 (1-2) ◽  
pp. 70-71
Author(s):  
P. Guidetti ◽  
H.-Q. Wu ◽  
R. Schwarcz
Keyword(s):  
Receptor Antagonist ◽  
Glycine Receptor

scholarly journals Spatiotemporal contribution of neuromesodermal progenitor-derived neural cells in the elongation of developing mouse spinal cord

2020 ◽  
Author(s):  
Mohammed R Shaker ◽  
Ju-Hyun Lee ◽  
Kyung Hyun Kim ◽  
Veronica Jihyun Kim ◽  
Joo Yeon Kim ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Neural Tube ◽  
Dorsal Side ◽  
Lineage Tracing ◽  
The Body ◽  
Lumbar Spinal Cord ◽  
Genetic Lineage ◽  
Mouse Development ◽  
Axial Elongation

ABSTRACTDuring vertebrate development, the posterior end of the embryo progressively elongates in a head-to-tail direction to form the body plan. Recent lineage tracing experiments revealed that bi-potent progenitors, called neuromesodermal progenitors (NMPs), produce caudal neural and mesodermal tissues during axial elongation. However, their precise location and contribution to spinal cord development remain elusive. Here we used NMP-specific markers (Sox2 and BraT) and a genetic lineage tracing system to localize NMP progeny in vivo. NMPs were initially located at the tail tip, but were later found in the caudal neural tube, which is a unique feature of mouse development. In the neural tube, they produced neural stem cells (NSCs) and contributed to the spinal cord gradually along the AP axis during axial elongation. Interestingly, NMP-derived NSCs preferentially contributed to the ventral side first and later to the dorsal side at the lumbar spinal cord level, which may be associated with atypical junctional neurulation in mice. Our current observations detail the contribution of NMP progeny to spinal cord elongation and provide insights into how different species uniquely execute caudal morphogenesis.

scholarly journals Characterization of DTI Indices in the Cervical, Thoracic, and Lumbar Spinal Cord in Healthy Humans

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Rachael L. Bosma ◽  
Patrick W. Stroman
Keyword(s):  
Spinal Cord ◽  
Mean Diffusivity ◽  
Lumbar Spinal Cord ◽  
Single Shot ◽  
Tissue Properties ◽  
Healthy Humans ◽  
Diffusion Weighted Images ◽  
Lumbar Spinal

The aim of this study was to characterizein vivomeasurements of diffusion along the length of the entire healthy spinal cord and to compare DTI indices, including fractional anisotropy (FA) and mean diffusivity (MD), between cord regions. The objective is to determine whether or not there are significant differences in DTI indices along the cord that must be considered for future applications of characterizing the effects of injury or disease. A cardiac gated, single-shot EPI sequence was used to acquire diffusion-weighted images of the cervical, thoracic, and lumbar regions of the spinal cord in nine neurologically intact subjects (19 to 22 years). For each cord section, FA versus MD values were plotted, and a k-means clustering method was applied to partition the data according to tissue properties. FA and MD values from both white matter (averageFA=0.69, averageMD=0.93×10−3 mm2/s) and grey matter (averageFA=0.44, averageMD=1.8×10−3 mm2/s) were relatively consistent along the length of the cord.

Sign in / Sign up

Export Citation Format

Share Document