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Just-Borràs L, Cilleros-Mañé V, Hurtado E, Biondi O, Charbonnier F, Tomàs M, Garcia N, Tomàs J, Lanuza MA. Running and Swimming Differently Adapt the BDNF/TrkB Pathway to a Slow Molecular Pattern at the NMJ. Int J Mol Sci 2021; 22:4577. [PMID: 33925507 PMCID: PMC8123836 DOI: 10.3390/ijms22094577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 04/22/2021] [Accepted: 04/23/2021] [Indexed: 12/29/2022] Open
Abstract
Physical exercise improves motor control and related cognitive abilities and reinforces neuroprotective mechanisms in the nervous system. As peripheral nerves interact with skeletal muscles at the neuromuscular junction, modifications of this bidirectional communication by physical activity are positive to preserve this synapse as it increases quantal content and resistance to fatigue, acetylcholine receptors expansion, and myocytes' fast-to-slow functional transition. Here, we provide the intermediate step between physical activity and functional and morphological changes by analyzing the molecular adaptations in the skeletal muscle of the full BDNF/TrkB downstream signaling pathway, directly involved in acetylcholine release and synapse maintenance. After 45 days of training at different intensities, the BDNF/TrkB molecular phenotype of trained muscles from male B6SJLF1/J mice undergo a fast-to-slow transition without affecting motor neuron size. We provide further knowledge to understand how exercise induces muscle molecular adaptations towards a slower phenotype, resistant to prolonged trains of stimulation or activity that can be useful as therapeutic tools.
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Affiliation(s)
- Laia Just-Borràs
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
| | - Víctor Cilleros-Mañé
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
| | - Erica Hurtado
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
| | - Olivier Biondi
- INSERM UMRS 1124, Université de Paris, CEDEX 06, F-75270 Paris, France; (O.B.); (F.C.)
| | - Frédéric Charbonnier
- INSERM UMRS 1124, Université de Paris, CEDEX 06, F-75270 Paris, France; (O.B.); (F.C.)
| | - Marta Tomàs
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
| | - Neus Garcia
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
| | - Josep Tomàs
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
| | - Maria A. Lanuza
- Unitat d’Histologia i Neurobiologia (UHNEUROB), Facultat de Medicina i Ciències de la Salut, Universitat Rovira i Virgili, 43201 Reus, Spain; (L.J.-B.); (V.C.-M.); (E.H.); (M.T.); (N.G.)
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Exercise modulates synaptic acetylcholinesterase at neuromuscular junctions. Neuroscience 2016; 319:221-32. [DOI: 10.1016/j.neuroscience.2016.01.044] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 12/31/2015] [Accepted: 01/19/2016] [Indexed: 11/22/2022]
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3
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Escames G, Ozturk G, Baño-Otálora B, Pozo MJ, Madrid JA, Reiter RJ, Serrano E, Concepción M, Acuña-Castroviejo D. Exercise and melatonin in humans: reciprocal benefits. J Pineal Res 2012; 52:1-11. [PMID: 21848991 DOI: 10.1111/j.1600-079x.2011.00924.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
The aim of this review is to update the reader as to the association between physical exercise and melatonin, and to clarify how the melatonin rhythm may be affected by different types of exercise. Exercise may act as a zeitgeber, although the effects of exercise on the human circadian system are only now being explored. Depending on the time of the day, on the intensity of light, and on the proximity of the exercise to the onset or decline of the circadian production of melatonin, the consequence of exercise on the melatonin rhythm varies. Moreover, especially strenuous exercise per se induces an increased oxidative stress that in turn may affect melatonin levels in the peripheral circulation because indole is rapidly used to combat free radical damage. On the other hand, melatonin also may influence physical performance, and thus, there are mutually interactions between exercise and melatonin production which may be beneficial.
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Affiliation(s)
- Germaine Escames
- Centro de Investigación Biomédica, Parque Tecnológico de Ciencias de la Salud, Universidad de Granada, Granada, Spain
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McCullough MJ, Peplinski NG, Kinnell KR, Spitsbergen JM. Glial cell line-derived neurotrophic factor protein content in rat skeletal muscle is altered by increased physical activity in vivo and in vitro. Neuroscience 2010; 174:234-44. [PMID: 21081155 DOI: 10.1016/j.neuroscience.2010.11.016] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2010] [Revised: 10/27/2010] [Accepted: 11/10/2010] [Indexed: 01/14/2023]
Abstract
Current evidence suggests that exercise and glial cell line-derived neurotrophic factor (GDNF) independently cause significant morphological changes in the neuromuscular system. The aim of the current study was to determine if increased physical activity regulates GDNF protein content in rat skeletal muscle. Extensor Digitorum Longus (EDL) and Soleus (SOL) hind limb skeletal muscles were analyzed following 2 weeks of involuntary exercise and 4 h of field stimulation or stretch in muscle bath preparations. GDNF protein content was measured via enzyme-linked immunosorbent assay (ELISA). Two weeks of exercise increased GDNF protein content in SOL as compared to sedentary controls (4.4±0.3 pg GDNF/mg tissue and 3.1±0.6 pg GDNF/mg tissue, respectively) and decreased GDNF protein content in EDL as compared to controls (1.0±0.1 pg GDNF/mg tissue and 2.3±0.7 pg GDNF/mg tissue, respectively). GDNF protein content in the EDL decreased following both field stimulation (56%±18% decrease from controls) and stretch (66%±10% decrease from controls). SOL responded to field stimulation with a 38%±7% increase from controls in GDNF protein content, but showed no change following stretch. Pre-treatment with α-bungarotoxin abolished the effects of field stimulation in both muscles and blocked the effect of stretch in EDL. α-bungarotoxin pre-treatment and stretch increased GDNF protein content to 240%±10% of controls in the SOL. Exposure to carbamylcholine decreased GDNF protein content to 51%±28% of controls in the EDL but not SOL. These results suggest that GDNF protein content in skeletal muscle may be controlled by stretch, where it may increase GDNF protein content, and membrane depolarization/acetylcholine (ACh) which acts to decrease GDNF protein content.
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Affiliation(s)
- M J McCullough
- Western Michigan University, Department of Biological Sciences, 1903 W. Michigan Avenue, Kalamazoo, MI 49008-5410, USA
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Wu X, Gao H, Xiao D, Luo S, Zhao Z. Effects of tensile stress on the α1 nicotinic acetylcholine receptor expression in maxillofacial skeletal myocytes. Mol Cell Biochem 2007; 311:51-6. [DOI: 10.1007/s11010-007-9693-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2007] [Accepted: 12/17/2007] [Indexed: 01/15/2023]
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7
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Mason SD, Rundqvist H, Papandreou I, Duh R, McNulty WJ, Howlett RA, Olfert IM, Sundberg CJ, Denko NC, Poellinger L, Johnson RS. HIF-1alpha in endurance training: suppression of oxidative metabolism. Am J Physiol Regul Integr Comp Physiol 2007; 293:R2059-69. [PMID: 17855495 DOI: 10.1152/ajpregu.00335.2007] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
During endurance training, exercising skeletal muscle experiences severe and repetitive oxygen stress. The primary transcriptional response factor for acclimation to hypoxic stress is hypoxia-inducible factor-1alpha (HIF-1alpha), which upregulates glycolysis and angiogenesis in response to low levels of tissue oxygenation. To examine the role of HIF-1alpha in endurance training, we have created mice specifically lacking skeletal muscle HIF-1alpha and subjected them to an endurance training protocol. We found that only wild-type mice improve their oxidative capacity, as measured by the respiratory exchange ratio; surprisingly, we found that HIF-1alpha null mice have already upregulated this parameter without training. Furthermore, untrained HIF-1alpha null mice have an increased capillary to fiber ratio and elevated oxidative enzyme activities. These changes correlate with constitutively activated AMP-activated protein kinase in the HIF-1alpha null muscles. Additionally, HIF-1alpha null muscles have decreased expression of pyruvate dehydrogenase kinase I, a HIF-1alpha target that inhibits oxidative metabolism. These data demonstrate that removal of HIF-1alpha causes an adaptive response in skeletal muscle akin to endurance training and provides evidence for the suppression of mitochondrial biogenesis by HIF-1alpha in normal tissue.
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MESH Headings
- Animals
- Blotting, Western
- Cells, Cultured
- Cyclic AMP-Dependent Protein Kinases/metabolism
- Erythrocyte Count
- Gene Expression/physiology
- Hematocrit
- Hemoglobins/metabolism
- Hypoxia-Inducible Factor 1, alpha Subunit/blood
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/physiology
- Mice
- Mice, Inbred C57BL
- Mice, Knockout
- Muscle, Skeletal/enzymology
- Muscle, Skeletal/metabolism
- Myoblasts/physiology
- Oxidation-Reduction
- Oxygen/blood
- Oxygen Consumption/genetics
- Oxygen Consumption/physiology
- Physical Conditioning, Animal/physiology
- Physical Endurance/physiology
- RNA, Messenger/biosynthesis
- RNA, Messenger/genetics
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Affiliation(s)
- Steven D Mason
- Div. of Biologicay, University of California, San Diego, La Jolla, CA 92093-0377, USA
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8
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Abstract
Evidence is presented that one locus of adaptation in the “neural adaptations to training” is at the level of the α-motoneurons. With increased voluntary activity, these neurons show evidence of dendrite restructuring, increased protein synthesis, increased axon transport of proteins, enhanced neuromuscular transmission dynamics, and changes in electrophysiological properties. The latter include hyperpolarization of the resting membrane potential and voltage threshold, increased rate of action potential development, and increased amplitude of the afterhyperpolarization following the action potential. Many of these changes demonstrate intensity-related adaptations and are in the opposite direction under conditions in which chronic activity is reduced. A five-compartment model of rat motoneurons that innervate fast and slow muscle fibers (termed “fast” and “slow” motoneurons in this paper), including 10 active ion conductances, was used to attempt to reproduce exercise training-induced adaptations in electrophysiological properties. The results suggest that adaptations in α-motoneurons with exercise training may involve alterations in ion conductances, which may, in turn, include changes in the gene expression of the ion channel subunits, which underlie these conductances. Interestingly, the acute neuromodulatory effects of monoamines on motoneuron properties, which would be a factor during acute exercise as these monoaminergic systems are activated, appear to be in the opposite direction to changes measured in endurance-trained motoneurons that are at rest. It may be that regular increases in motoneuronal excitability during exercise via these monoaminergic systems in fact render the motoneurons less excitable when at rest. More research is required to establish the relationships between exercise training, resting and exercise motoneuron excitability, ion channel modulation, and the effects of neuromodulators.
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Affiliation(s)
- P Gardiner
- Department of Physiology, Spinal Cord Research Center, University of Manitoba, 730 William Ave., Winnipeg, Manitoba, Canada R3E 3J7.
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Desaulniers P, Lavoie PA, Gardiner PF. Effect of rat soleus muscle overload on neuromuscular transmission efficacy during continuous and intermittent activation. Exp Physiol 2005; 90:333-40. [PMID: 15640276 DOI: 10.1113/expphysiol.2004.029132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Increased neuromuscular activity is known to provoke morphological and functional adaptations at the neuromuscular synapse. Most of these changes have been documented following endurance exercise training programmes. In this study, the effect of rat soleus muscle overload produced by tenotomy plus voluntary wheel-cage activity on neuromuscular transmission efficacy was investigated. The overload protocol increased miniature endplate potential (MEPP) and endplate potential (EPP) amplitudes by 17 and 19%, respectively (both P < 0.01), and increased MEPP frequency by 86% (P < 0.01). EPP amplitude rundown during continuous trains of activation was attenuated by approximately 10% in the overloaded group (P < 0.01). Also, during intermittent activation, the overload protocol attenuated EPP amplitude rundown, mainly by enhancing EPP amplitude recovery by approximately 10% during the quiescent periods (P < 0.01). Although the present results show that both the degree and direction of adaptation are similar to what has been observed at rat soleus neuromuscular junctions following an endurance training protocol, there are important nuances between the results, suggesting different mechanisms through which these changes may occur.
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Cavalcante WLG, Dal Pai-Silva M, Gallacci M. Effects of nandrolone decanoate on the neuromuscular junction of rats submitted to swimming. Comp Biochem Physiol C Toxicol Pharmacol 2004; 139:219-24. [PMID: 15683830 DOI: 10.1016/j.cca.2004.11.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Revised: 11/10/2004] [Accepted: 11/14/2004] [Indexed: 11/18/2022]
Abstract
This study addressed the effects of nandrolone decanoate (ND) on contractile properties and muscle fiber characteristics of rats submitted to swimming. Male Wistar rats were grouped in sedentary (S), swimming (Sw), sedentary+ND (SND), and swimming+ND (SwND), six animals per group. ND (3 mg/kg) was injected (subcutaneously) 5 days/week, for 4 weeks. Swimming consisted of 60-min sessions (load 2%), 5 days/week, for 4 weeks. After this period, the sciatic nerve extensor digitorum longus (EDL) muscle was isolated for myographic recordings. Fatigue resistance was assessed by the percent (%) decline of 180 direct tetanic contractions (30 Hz). Safety margin of synaptic transmission was determined from the resistance to the blockade of indirectly evoked twitches (0.5 Hz) induced by pancuronium (5 to 9x10(-7) M). EDL muscles were also submitted to histological and histochemical analysis (haematoxylin-eosin (HE); nicotinamide adenine dinucleotide-tetrazolium reductase (NADH-TR)). Significant differences were detected by two-way ANOVA (p<0.05). ND did not change body mass, fatigue resistance or kinetic properties of indirect twitches in either sedentary or swimming rats. In contrast, ND reduced the safety margin of synaptic transmission in sedentary animals (SND=53.3+/-4.7% vs. S=75.7+/-2.0%), but did not affect the safety margin in the swimming rats (SwND=75.81+/-3.1% vs. Sw=71.0+/-4.0%). No significant difference in fiber type proportions or diameters was observed in EDL muscle of any experimental group. These results indicate that ND does not act as an ergogenic reinforcement in rats submitted to 4 weeks of swimming. On the other hand, this study revealed an important toxic effect of ND, that it reduces the safety margin of synaptic transmission in sedentary animals. Such an effect is masked when associated with physical exercise.
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Affiliation(s)
- W L G Cavalcante
- Department of Pharmacology, Institute of Bioscience, University Estadual Paulista (Unesp), Botucatu, São Paulo, CEP 18618-000, Brazil
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11
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Argaw A, Desaulniers P, Gardiner PF. Enhanced neuromuscular transmission efficacy in overloaded rat plantaris muscle. Muscle Nerve 2004; 29:97-103. [PMID: 14694504 DOI: 10.1002/mus.10535] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
To better understand the effect of muscle hypertrophy on the physiological properties of transmitter release, we investigated neuromuscular transmission (NMT) efficacy in overloaded rat plantaris muscle in situ. In the overload group, following bilateral tenotomy of plantaris synergists, rats were confined to wheel-cages. Age-matched rats in the control group were confined to plastic cages. During the terminal experiment, muscle action potentials were blocked using micro-conotoxin, and full-sized endplate potentials (EPPs) were recorded at 25, 50, and 75 HZ to determine their amplitude rundown. Quantal contents for the control and overload groups were 37.0 and 74.3, respectively (P <0.01). There was a significant group difference in EPP amplitude rundown at all frequencies examined, with increased rundown occurring in the overload group (P < 0.01). Cumulative quantal release was 139% and 153% higher in the overload group at 25 and 50 HZ, respectively (P < 0.05). Together, these data suggest the safety factor for NMT is increased by neuromuscular overload. Furthermore, these findings support and supplement previously reported activity-dependent improvements in NMT efficacy that are probably mediated via presynaptic adaptations.
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Affiliation(s)
- Anteneh Argaw
- Department of Kinesiology, University of Montreal, C.P. 6128, Succursale Centre-Ville, Montreal, Canada
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12
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Wehrwein EA, Roskelley EM, Spitsbergen JM. GDNF is regulated in an activity-dependent manner in rat skeletal muscle. Muscle Nerve 2002; 26:206-11. [PMID: 12210384 DOI: 10.1002/mus.10179] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Glial cell line-derived neurotrophic factor (GDNF) is produced by skeletal muscle and affects peripheral motor neurons. Elevated expression of GDNF in skeletal muscle leads to hyperinnervation of neuromuscular junctions, whereas postnatal administration of GDNF causes synaptic remodeling at the neuromuscular junction. Studies have demonstrated that altered physical activity causes changes in the neuromuscular junction. However, the role played by GDNF in this process in not known. The objective of this study was to determine whether changes in neuromuscular activity cause altered GDNF content in rat skeletal muscle. Following 4 weeks of walk-training on a treadmill, or 2 weeks of hindlimb unloading, soleus, gastrocnemius, and pectoralis major were removed and analyzed for GDNF content by enzyme-linked immunosorbant assay. Results indicated that walk-training is associated with increased GDNF content. Skeletal muscle from hindlimb-unloaded animals showed a decrease in GDNF in soleus and gastrocnemius, and an increase in pectoralis major. The altered production of GDNF may be responsible for activity-dependent remodeling of the neuromuscular junction and may aid in recovery from injury and disease.
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Affiliation(s)
- Erica A Wehrwein
- Department of Biological Sciences, Western Michigan University, Kalamazoo, Michigan 49008, USA
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Desaulniers P, Lavoie PA, Gardiner PF. Habitual exercise enhances neuromuscular transmission efficacy of rat soleus muscle in situ. J Appl Physiol (1985) 2001; 90:1041-8. [PMID: 11181618 DOI: 10.1152/jappl.2001.90.3.1041] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Rat motor nerve terminals and the endplates they interact with exhibit changes to varying patterns of use, as when exposed to increased activation in the form of endurance exercise training. The extent to which these changes affect neuromuscular transmission efficacy is uncertain. In this study, the effects of habitual exercise on the electrophysiological properties of neuromuscular transmission in rat soleus muscle were investigated using a novel in situ approach. Consistent with previous reports, miniature endplate potential frequency was enhanced by habitual exercise. Other passive properties, such as resting membrane potential, miniature endplate potential amplitude, and "giant" miniature endplate potential characteristics were unaltered by the training program. Full-size endplate potentials were obtained by blocking soleus muscle action potentials with mu-conotoxin GIIIb. Quantal content values were 91.5 and 119.9 for control and active groups, respectively (P < 0.01). We also measured the rate and extent of endplate potential amplitude rundown during 3-s trains of continuous stimulation at 25, 50, and 75 Hz; at 50 and 75 Hz, we found both the rate and extent of rundown to be significantly attenuated (10--20%) in a specific population of cells from active rats (P < 0.05). The results establish the degree of activity-dependent plasticity as it pertains to neuromuscular transmission in a mammalian slow-twitch muscle.
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Affiliation(s)
- P Desaulniers
- Département de Kinésiologie, Université de Montréal, Montréal, Québec, Canada H3C 3J7
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14
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Deschenes MR, Judelson DA, Kraemer WJ, Meskaitis VJ, Volek JS, Nindl BC, Harman FS, Deaver DR. Effects of resistance training on neuromuscular junction morphology. Muscle Nerve 2000; 23:1576-81. [PMID: 11003794 DOI: 10.1002/1097-4598(200010)23:10<1576::aid-mus15>3.0.co;2-j] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The aim of this study was to determine the impact of resistance exercise on neuromuscular junction (NMJ) architecture. Eighteen Sprague-Dawley rats either participated in a 7-week resistance training program or served as untrained controls. Following the experimental period, the NMJs of soleus muscles were visualized with immunofluorescent techniques, and muscle fibers were stained histochemically. Results indicate that resistance training significantly (P < 0.05) increased endplate perimeter length (15%) and area (16%), and significantly enhanced the dispersion of acetylcholine receptors within the endplate region. Pre- and post-synaptic modifications to resistance exercise were well-coupled. No significant alterations in muscle fiber size or fiber type were detected. The data presented here indicate that the stimulus of resistance training was sufficiently potent to remodel NMJ structure, and that this effect cannot be attributed to muscle fiber hypertrophy or fiber type conversion.
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Affiliation(s)
- M R Deschenes
- Department of Kinesiology, College of William and Mary, Williamsburg, Virginia 23187-8795, USA.
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