Acetylcholine release from fetal tissue homotopically grafted to the motoneuron-depleted lumbar spinal cord. An in vivo microdialysis study in the awake rat

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.

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Inhibition of synaptically evoked cortical acetylcholine release by adenosine: an in vivo microdialysis study in the rat

Neuroscience ◽

10.1016/s0306-4522(00)00075-0 ◽

2000 ◽

Vol 97 (2) ◽

pp. 219-226 ◽

Cited By ~ 29

Author(s):

L.M Materi ◽

D.D Rasmusson ◽

K Semba

Keyword(s):

Acetylcholine Release ◽

In Vivo Microdialysis ◽

Microdialysis Study

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Extracellular cholecystokinin levels in the rat spinal cord following chronic morphine exposure: an in vivo microdialysis study

Brain Research ◽

10.1016/s0006-8993(99)01068-9 ◽

1999 ◽

Vol 821 (1) ◽

pp. 79-86 ◽

Cited By ~ 7

Author(s):

Guilherme de Araujo Lucas ◽

Orsolya Hoffmann ◽

Pawel Alster ◽

Zsuzsanna Wiesenfeld-Hallin

Keyword(s):

Spinal Cord ◽

In Vivo Microdialysis ◽

Rat Spinal Cord ◽

Chronic Morphine ◽

Microdialysis Study

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Long-term effects on cortical glutamate release induced by prenatal exposure to the cannabinoid receptor agonist (r)-(+)-[2,3-dihydro-5-methyl-3-(4-morpholinyl-methyl)pyrrolo[1,2,3-de]-1,4-benzoxazin-6-yl]-1-naphthalenylmethanone: an in vivo microdialysis study in the awake rat

Neuroscience ◽

10.1016/j.neuroscience.2003.10.034 ◽

2004 ◽

Vol 124 (2) ◽

pp. 367-375 ◽

Cited By ~ 28

Author(s):

T Antonelli ◽

S Tanganelli ◽

M.C Tomasini ◽

S Finetti ◽

L Trabace ◽

...

Keyword(s):

Prenatal Exposure ◽

Receptor Agonist ◽

Cannabinoid Receptor ◽

Glutamate Release ◽

In Vivo Microdialysis ◽

Long Term Effects ◽

Awake Rat ◽

Microdialysis Study

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An in vivo method for recording single unit activity in lumbar spinal cord in mice anesthetized with a volatile anesthetic

Brain Research Protocols ◽

10.1016/j.brainresprot.2004.03.002 ◽

2004 ◽

Vol 13 (2) ◽

pp. 126-134 ◽

Cited By ~ 6

Author(s):

Jason M Cuellar ◽

Joseph F Antognini ◽

Earl Carstens

Keyword(s):

Spinal Cord ◽

Unit Activity ◽

Single Unit ◽

Volatile Anesthetic ◽

Lumbar Spinal Cord ◽

Single Unit Activity ◽

Lumbar Spinal

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

Radiology Research and Practice ◽

10.1155/2012/143705 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 5

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.

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