scholarly journals AN ELECTRON MICROSCOPE STUDY OF CULTURED RAT SPINAL CORD

1965 ◽  
Vol 24 (2) ◽  
pp. 163-191 ◽  
Author(s):  
Richard P. Bunge ◽  
Mary Bartlett Bunge ◽  
Edith R. Peterson
Keyword(s):  
Spinal Cord ◽  
Synaptic Vesicles ◽  
Light And Electron Microscopy ◽  
Structure Type ◽  
Rat Spinal Cord ◽  
Fetal Rat ◽  
Synaptic Junctions ◽  
Axodendritic Synapses

Explants prepared from 17- to 18-day fetal rat spinal cord were allowed to mature in culture; such preparations have been shown to differentiate and myelinate in vitro (61) and to be capable of complex bioelectric activity (14–16). At 23, 35, or 76 days, the cultures were fixed (without removal from the coverslip) in buffered OsO4, embedded in Epon, sectioned, and stained for light and electron microscopy. These mature explants generally are composed of several strata of neurons with an overlying zone of neuropil. The remarkable cytological similarity between in vivo and in vitro nervous tissues is established by the following observations. Cells and processes in the central culture mass are generally closely packed together with little intervening space. Neurons exhibit well developed Nissl bodies, elaborate Golgi regions, and subsurface cisternae. Axosomatic and axodendritic synapses, including synaptic junctions between axons and dendritic spines, are present. Typical synaptic vesicles and increased membrane densities are seen at the terminals. Variations in synaptic fine structure (Type 1 and Type 2 synapses of Gray) are visible. Some characteristics of the cultured spinal cord resemble infrequently observed specializations of in vivo central nervous tissue. Neuronal somas may display minute synapse-bearing projections. Occasionally, synaptic vesicles are grouped in a crystal-like array. A variety of glial cells, many apparently at intermediate stages of differentiation, are found throughout the otherwise mature explant. There is ultrastructural evidence of extensive glycogen deposits in some glial processes and scattered glycogen particles in neuronal terminals. This is the first description of the ultrastructure of cultured spinal cord. Where possible, correlation is made between the ultrastructural data and the known physiological properties of these cultures.

A Novel In Vitro Approach for Studying the Segmental Motor System

Physiology ◽  
1992 ◽  
Vol 7 (6) ◽  
pp. 249-253
Author(s):  
H-R Luscher ◽  
J Streit
Keyword(s):  
Spinal Cord ◽  
Culture System ◽  
In Vitro Model ◽  
Organotypic Culture ◽  
Rat Spinal Cord ◽  
Structural And Functional Properties ◽  
Spinal Cord Dorsal ◽  
Vitro Model

An organotypic culture system of rat spinal cord, dorsal root ganglia, and skeletal muscle is presented that develops and preserves many structural and functional properties of the in vivo spinal cord. This in vitro model enlarges the methodological repertoire of mammalian spinal cord physiology and is ideally suited for studying developmental aspects.

Microdialysis of galanin in rat spinal cord: in vitro and in vivo studies

2001 ◽  
Vol 139 (3) ◽  
pp. 354-358 ◽  
Author(s):  
Hygge Blakeman ◽  
Z. Wiesenfeld-Hallin ◽  
P. Alster
Keyword(s):  
Spinal Cord ◽  
In Vivo Studies ◽  
Rat Spinal Cord

Neuroepithelial cells in the rat spinal cord express glutamate decarboxylase immunoreactivity in vivo and in vitro

1992 ◽  
Vol 325 (2) ◽  
pp. 257-270 ◽  
Author(s):  
Wu Ma ◽  
Toby Behar ◽  
Dragan Maric ◽  
Irina Maric ◽  
Jeffery L. Barker
Keyword(s):  
Spinal Cord ◽  
Glutamate Decarboxylase ◽  
Rat Spinal Cord ◽  
Neuroepithelial Cells

Coapplication of noisy patterned electrical stimuli and NMDA plus serotonin facilitates fictive locomotion in the rat spinal cord

2012 ◽  
Vol 108 (11) ◽  
pp. 2977-2990 ◽  
Author(s):  
Francesco Dose ◽  
Giuliano Taccola
Keyword(s):  
Spinal Cord ◽  
Fictive Locomotion ◽  
Rat Spinal Cord ◽  
High Potassium ◽  
Pharmacological Agents ◽  
Afferent Fibers ◽  
Locomotor Patterns ◽  
Vitro Model

A new stimulating protocol [fictive locomotion-induced stimulation (FL istim)], consisting of intrinsically variable weak waveforms applied to a single dorsal root is very effective (though not optimal as it eventually wanes away) in activating the locomotor program of the isolated rat spinal cord. The present study explored whether combination of FL istim with low doses of pharmacological agents that raise network excitability might further improve the functional outcome, using this in vitro model. FL istim was applied together with N-methyl-d-aspartate (NMDA) + serotonin, while fictive locomotion (FL) was electrophysiologically recorded from lumbar ventral roots. Superimposing FL istim on FL evoked by these neurochemicals persistently accelerated locomotor-like cycles to a set periodicity and modulated cycle amplitude depending on FL istim rate. Trains of stereotyped rectangular pulses failed to replicate this phenomenon. The GABAB agonist baclofen dose dependently inhibited, in a reversible fashion, FL evoked by either FL istim or square pulses. Sustained episodes of FL emerged when FL istim was delivered, at an intensity subthreshold for FL, in conjunction with subthreshold pharmacological stimulation. Such an effect was, however, not found when high potassium solution instead of NMDA + serotonin was used. These results suggest that the combined action of subthreshold FL istim (e.g., via epidural stimulation) and neurochemicals should be tested in vivo to improve locomotor rehabilitation after injury. In fact, reactivation of spinal locomotor circuits by conventional electrical stimulation of afferent fibers is difficult, while pharmacological activation of spinal networks is clinically impracticable due to concurrent unwanted effects. We speculate that associating subthreshold chemical and electrical inputs might decrease side effects when attempting to evoke human locomotor patterns.

Acetylcholine Stimulates the Release of Nitric Oxide from Rat Spinal Cord

1996 ◽  
Vol 85 (1) ◽  
pp. 107-111 ◽  
Author(s):  
Zemin Xu ◽  
Chuanyao Tong ◽  
James C. Eisenach
Keyword(s):  
Nitric Oxide ◽  
Spinal Cord ◽  
Spinal Cord Tissue ◽  
Rat Spinal Cord ◽  
Nitric Oxide Release ◽  
Nervous System Activity ◽  
Oxide Synthase ◽  
Anatomic Localization

Background Acetylcholine causes synthesis of nitric oxide in vascular endothelium, and presumptive evidence in vivo suggests spinally released acetylcholine causes antinociception and increased sympathetic nervous system activity via a nitric oxide mechanism. The purpose of this study was to determine, using a recently described bioassay system, whether acetylcholine stimulates nitric oxide release from spinal cord tissue in vitro. Methods Rat thoracolumbar spinal cord slices were incubated in a tissue chamber and perfused with Krebs-Henseleit solution. The perfusate was then passed through endotheliumdenuded rat aortic rings and their tension was measured. Vascular rings were preconstricted with phenylephrine, then were exposed to spinal cord perfusate with increasing concentrations (10(-12)-10(-4)M) of acetylcholine alone or with various antagonists. Results Acetylcholine perfusion of spinal tissue caused concentration-dependent relaxations of the aortic rings, an effect blocked by each of the muscarinic antagonists, atropine, pirenzepine, and AFDX-116. Acetylcholine-induced relaxation also was antagonized by an inhibitor of nitric oxide synthase (N-methyl-L-arginine), a nitric oxide scavenger (hemoglobin) and an inhibitor of guanylate cyclase (methylene blue). Conclusions These results demonstrate release of a vasorelaxant from spinal cord tissue by acetylcholine, which results from an action on muscarinic receptors and exhibits a pharmacology consistent with nitric oxide. Although precise anatomic localization of acetylcholine's action is not possible with this system, these results add to evidence that acetylcholine causes nitric oxide synthesis in the spinal cord.

The action of quinolinate in the rat spinal cord in vitro

1987 ◽  
Vol 65 (12) ◽  
pp. 2483-2487 ◽  
Author(s):  
D. S. K. Magnuson ◽  
M. J. Peet ◽  
K. Curry ◽  
H. McLennan
Keyword(s):  
Spinal Cord ◽  
Amino Acid ◽  
Rat Spinal Cord ◽  
Response Curves ◽  
Bathing Medium ◽  
Amino Acid Receptors ◽  
Dorsal Horn Neurones ◽  
Medium Dose

The responses of dorsal horn neurones to the excitatory amino acids quisqualate, kainate, N-methyl-D-aspartate (NMDA), and quinolinate have been examined in an in vitro preparation of the rat spinal cord. The antagonism of these responses by iontophoretically applied D-(−)-2-amino-5-phosphonovalerate (DAPV), kynurenate, and acridinate was tested, and the results were compared with data obtained from the spinal cord in vivo. The pattern of antagonism was similar in both preparations, although the potencies of agonists and antagonists were found to be significantly greater in vitro. The antagonism of amino acid induced firing of neurones was also recorded during the application of DAPV and kynurenate in the bathing medium. Dose–response curves and IC50 values were determined for these antagonists against all four agonists. The responses to quinolinate were antagonized differently from those to NMDA, quisqualate, or kainate, suggesting that quinolinate does not act specifically through the NMDA receptor as it does in other regions, nor does it appear to act via two or more of the three archetypal amino acid receptors. These findings suggest that a fourth amino acid receptor responsible for quinolinate's action in the spinal cord may exist.

Sign in / Sign up

Export Citation Format

Share Document