Activities of acetylcholinesterase, choline acetyltransferase, and catecholamine production in the spinal cord of the axolotl Ambystoma mexicanum during forelimb regeneration

1994 ◽  
Vol 72 (5-6) ◽  
pp. 188-194 ◽  
Author(s):  
Patrick Scaps ◽  
François Bernet ◽  
Jean Gautron ◽  
Bénoni Boilly
Keyword(s):  
Spinal Cord ◽  
Molecular Weight ◽  
Choline Acetyltransferase ◽  
Control Level ◽  
Limb Regeneration ◽  
Nerve Fibers ◽  
Ambystoma Mexicanum ◽  
Limb Amputation ◽  
Metabolic Activities ◽  
Molecular Weight Form

Amputation of an axolotl limb causes severance of the brachial nerves, followed by their regeneration into a blastema. It is known that these nerves provide a neurotophic factor to blastemal cells. To approach the problem of the response of spinal cord nerve centers to forelimb amputation, we have studied biosynthetic activities in the nerve centers involved in axonal injury during limb regeneration. We report that the acetylcholinesterase (AChE) activity in the spinal cord is elevated 2 days (+ 69%) and 7 days (+ 28%) after limb amputation compared with levels in unamputated control animals, but is not significantly elevated at 3 h or 15 days. The percentages of slow (3.6 S and 6.0 S) and fast (18 S) sedimenting forms of AChE progressively decrease 2 and 7 days after amputation, while those of intermediate sedimenting forms (10.5 S and 14.0 S) increase. Fifteen days after amputation, lower molecular weight forms return to the control level, but the heavy molecular weight form of AChE is absent as at 7 days; consequently intermediate molecular weight forms are in a greater proportion than the other two forms. Choline acetyltransferase activity was measured only 2 days after amputation (when AChE was at its highest level). It increases by about 34% with regard to the controls. Adrenaline is higher than controls 2 days after amputation, while noradrenaline is not significantly modified. The metabolic changes observed in the spinal cord during limb regeneration probably are the result of a general reaction to the stress of amputation (transection of brachial nerves) and regeneration of nerve fibers, since similar metabolic activities were observed after a simple denervation of the two unamputated forelimbs.Key words: acetylcholinesterase, choline acetyltransferase, catecholamines, regeneration, axolotl.

Vitamin A modification of the positional information of blastema cells during limb regeneration in the axolotl Ambystoma mexicanum

1988 ◽  
Vol 66 (9) ◽  
pp. 2065-2070 ◽  
Author(s):  
Steven R. Scadding
Keyword(s):  
Vitamin A ◽  
Limb Regeneration ◽  
Normal Structure ◽  
Positional Information ◽  
Ambystoma Mexicanum ◽  
Limb Amputation ◽  
Temporary Change ◽  
Cellular Changes ◽  
Regeneration Blastema

Vitamin A is known to cause proximodistal duplication of parts of the limb during limb regeneration in amphibians. The objective of this study was to investigate the nature and location of the cellular changes induced by vitamin A when it causes this duplication in the axolotl Ambystoma mexicanum. When axolotls were treated with retinol palmitate by immersion for 14 days before limb amputation, proximodistal duplications were still observed in subsequent regenerates of limbs amputated after vitamin A treatment was discontinued. This observation suggests that some characteristic of the cells is changed by vitamin A and that exogenous vitamin A need not be present while the limb is regenerating. When a limb that was induced to undergo proximodistal duplication by vitamin A was reamputated 49 days later through the original mid radius–ulna amputation plane, it regenerated a limb of normal structure. A regeneration blastema transplanted from a vitamin A treated axolotl to an untreated axolotl regenerated on the host limb stump, producing a limb with proximodistal duplication; this indicates that the blastema cells underwent some change by the early to mid cone stage, which was expressed later when the blastema redifferentiated into a new limb. Conversely, when an untreated blastema was transplanted onto a vitamin A treated axolotl from which the forelimb blastema had been removed, proximodistal duplications developed. This result is interpreted to mean that the stump cells, although morphologically of the radius–ulna level, were proximalized by the prior vitamin A treatment and still displayed proximal positional values, leading to intercalation of missing proximodistal structures. These results are consistent with the hypothesis that vitamin A brings about a temporary change in the positional information of the limb stump and blastema cells, and that when the vitamin A treatment is discontinued, there is a gradual return to normal positional values over a period of several weeks.

scholarly journals Comparison of Gene Expression During Early Phases of Limb Regeneration Between Regeneration-permissive Neotenic and Regeneration-deficient Metamorphic Axolotl

2019 ◽  
Author(s):  
Mustafa Sibai ◽  
Ebru Altuntaş ◽  
Barış Ethem Süzek ◽  
Betül Şahin ◽  
Cüneyd Parlayan ◽  
...  
Keyword(s):  
Immune System ◽  
Limb Regeneration ◽  
Principal Component ◽  
Ambystoma Mexicanum ◽  
Functional Enrichment ◽  
Limb Amputation ◽  
Regenerative Capacity ◽  
Ecm Remodeling ◽  
Blastema Formation ◽  
Early Phases

ABSTRACTThe axolotl (Ambystoma Mexicanum) salamander, an urodele amphibian, has an exceptional regenerative capacity to fully restore an amputated limb throughout the life-long lasting neoteny. By contrast, when axolotls are experimentally induced to metamorphosis, attenuation of the limb’s regenerative competence is noticeable. Here, we sought to discern the proteomic profiles of the early stages of blastema formation of neotenic and metamorphic axolotls after limb amputation by means of LC-MS/MS technology. We quantified a total of 714 proteins having an adjusted p < 0.01 with FC greater or equal to 2 between two conditions. Principal component analysis revealed a conspicuous clustering between neotenic and metamorphic samples at 7 days post-amputation. Different set of proteins was identified as differentially expressed at all of the time points (1, 4, and 7 days post-amputations against day0) for neotenic and metamorphic stages. Although functional enrichment analyses underline the presence of common pathways between regenerative and nonregenerative stages, cell proliferation and its regulation associated pathways, immune system related pathways and muscle tissue and ECM remodeling and degradation pathways were represented at different rate between both stages. To validate the proteomics results and provide evidence for the putative link between immune system activity and regenerative potential, qRT-PCR for selected genes was performed.

scholarly journals Choline acetyltransferase activity of spinal cord cell cultures increased by co-culture with muscle and by muscle-conditioned medium

1977 ◽  
Vol 74 (1) ◽  
pp. 16-29 ◽  
Author(s):  
EL Giller ◽  
JH Neale ◽  
PN Bullock ◽  
BK Schrier ◽  
PG Nelson
Keyword(s):  
Spinal Cord ◽  
Molecular Weight ◽  
Conditioned Medium ◽  
Choline Acetyltransferase ◽  
Membrane Filtration ◽  
Active Material ◽  
Muscle Cells ◽  
Blocking Agent ◽  
Acid Decarboxylase ◽  
Undifferentiated Cells

Activity of the enzyme choline acetyltransferase (CAT), which mediates the synthesis of the neurotransmitter, acetylcholine, was increased up to 20- fold in spinal cord (SC) cells grown in culture with muscle cells for 2 wk. This increase was directly related to the duration of co-culture as well as to the cell density of both the SC and muscle involved and was not affected by the presence of the acetylcholine receptor blocking agent, α-bungarotoxin. Glutamic acid decarboxylase (GAD) activity was often markedly decreased in SC-muscle cultures while the activities of acetylcholinesterase and several other enzymes were little changed. Increased CAT activity was also observed when SC cultures were maintained in medium which had been conditioned by muscle cells or by undifferentiated cells from embryonic muscle. Muscle-conditioned medium (CM) did not affect the activities of SC cell GAD or acetylcholinesterase. Dilution or concentration of the CM directly affected its ability to increase SC CAT activity , as did the duration and timing of exposure of the SC cells to the CM. The medium could be conditioned by muscle cells in the presence or absence of serum, and remained effective after dialysis or heating to 58 degrees C. Membrane filtration data were consistent with the conclusion that the active material(s) in CM had a molecular weight in excess of 50,000 daltons. We conclude that large molecular weight material that is released by muscle cells is capable of producing a specific increase in CAT activity of SC cells.

scholarly journals Successful application of burst spinal cord stimulation for refractory upper limb pain: a case series

2021 ◽  
Vol 49 (3) ◽  
pp. 030006052110040
Author(s):  
Kuen Su Lee ◽  
Yoo Kyung Jang ◽  
Gene Hyun Park ◽  
In Jae Jun ◽  
Jae Chul Koh
Keyword(s):  
Spinal Cord ◽  
Upper Limb ◽  
Spinal Cord Stimulation ◽  
Therapeutic Potential ◽  
Case Series ◽  
Limb Amputation ◽  
Intractable Pain ◽  
Limb Pain ◽  
Cord Injury ◽  
Upper Limb Pain

Spinal cord stimulation (SCS) has been used to treat sustained pain that is intractable despite various types of treatment. However, conventional tonic waveform SCS has not shown promising outcomes for spinal cord injury (SCI) or postamputation pain. The pain signal mechanisms of burst waveforms are different to those of conventional tonic waveforms, but few reports have presented the therapeutic potential of burst waveforms for the abovementioned indications. This current case report describes two patients with refractory upper limb pain after SCI and upper limb amputation that were treated with burst waveform SCS. While the patients could not obtain sufficient therapeutic effect with conventional tonic waveforms, the burst waveforms provided better pain reduction with less discomfort. However, further studies are necessary to better clarify the mechanisms and efficacy of burst waveform SCS in patients with intractable pain.

scholarly journals The Purification of Low Molecular Weight Form of Polypeptide Elongation Factor 1 from Pig Liver

1974 ◽  
Vol 249 (15) ◽  
pp. 5008-5010
Author(s):  
Kentaro Iwasaki ◽  
Shigekazu Nagata ◽  
Kiyohisa Mizumoto ◽  
Yoshito Kaziro
Keyword(s):  
Molecular Weight ◽  
Elongation Factor ◽  
Low Molecular Weight ◽  
Pig Liver ◽  
Elongation Factor 1 ◽  
Molecular Weight Form
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