Vascular-Interstitial-Neuromuscular Circuits in Neuromuscular Activation: Differences in Femoral and Sciatic Nerves in the Rat

Several speculations exist as to the site of incorporation of preformed molecules into myelin. The possibility that an autoradiographic analysis of cholesterol-1,2-H3 incorporation at very short times after injection might shed some light in the solution of that problem led to the present experiment.Cholesterol-1,2-H3 was injected intraperitoneally into 24 tenday old mice. The animals were then sacrificed at 10,20,30,40,60,90,120 and 180 min after the injection and the sciatic nerves were processed for electron microscope autoradiography. To analyze the grain distribution in the autoradiograms of cross and longitudinal sections from each sciatic nerve myelin sheaths were subdivided into three compartments named: outer 1/3, middle 1/3 and inner 1/3 compartments.It was found that twenty min. after the injection of cholesterol -1.2-H3 (Figs. 1 and 2), 55% of the total number of grains (t.n.g) found in myelin were within the outer 1/3 compartment, 9% were within the middle 1/3 and 36% within the inner 1/3 compartment

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Alternations of substance P and its processing eenzymes after the ligation of rat sciatic nerves in rat dorsal root gamglia associated with allodynia

Neuroscience Research ◽

10.1016/s0168-0102(00)81209-2 ◽

2000 ◽

Vol 38 ◽

pp. S60

Author(s):

K Tsuchida

Keyword(s):

Substance P ◽

Dorsal Root ◽

Sciatic Nerves

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People with chronic ankle instability benefit from brace application in highly dynamic change of direction movements

Journal of Foot and Ankle Research ◽

10.1186/s13047-021-00452-0 ◽

2021 ◽

Vol 14 (1) ◽

Author(s):

Patrick Fuerst ◽

Albert Gollhofer ◽

Markus Wenning ◽

Dominic Gehring

Keyword(s):

Ankle Joint ◽

Repeated Measures ◽

Ankle Instability ◽

Dynamic Change ◽

Chronic Ankle Instability ◽

Mechanical Resistance ◽

Healthy Controls ◽

Neuromuscular Activation ◽

Ankle Inversion ◽

Ankle Brace

Abstract Background The application of ankle braces is an effective method for the prevention of recurrent ankle sprains. It has been proposed that the reduction of injury rates is based on the mechanical stiffness of the brace and on beneficial effects on proprioception and neuromuscular activation. Yet, how the neuromuscular system responds to the application of various types of ankle braces during highly dynamic injury-relevant movements is not well understood. Enhanced stability of the ankle joint seems especially important for people with chronic ankle instability. We therefore aimed to analyse the effects of a soft and a semi-rigid ankle brace on the execution of highly dynamic 180° turning movements in participants with and without chronic ankle instability. Methods Fifteen participants with functional ankle instability, 15 participants with functional and mechanical ankle instability and 15 healthy controls performed 180° turning movements in reaction to light signals in a cross-sectional descriptive laboratory study. Ankle joint kinematics and kinetics as well as neuromuscular activation of muscles surrounding the ankle joint were determined. Two-way repeated measures analyses of variance and post-hoc t-tests were calculated. Results Maximum ankle inversion angles and velocities were significantly reduced with the semi-rigid brace in comparison to the conditions without a brace and with the soft brace (p ≤ 0.006, d ≥ 0.303). Effect sizes of these reductions were larger in participants with chronic ankle instability than in healthy controls. Furthermore, peroneal activation levels decreased significantly with the semi-rigid brace in the 100 ms before and after ground contact. No statistically significant brace by group effects were found. Conclusions Based on these findings, we argue that people with ankle instability in particular seem to benefit from a semi-rigid ankle brace, which allows them to keep ankle inversion angles in a range that is comparable to values of healthy people. Lower ankle inversion angles and velocities with a semi-rigid brace may explain reduced injury incidences with brace application. The lack of effect of the soft brace indicates that the primary mechanism behind the reduction of inversion angles and velocities is the mechanical resistance of the brace in the frontal plane.

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The Effects of Verbal Cueing for High Intended Movement Velocity on Power, Neuromuscular Activation and Performance.

Scandinavian Journal of Medicine and Science in Sports ◽

10.1111/sms.13926 ◽

2021 ◽

Author(s):

Michael Rheese ◽

Eric J. Drinkwater ◽

Hans Leung ◽

Justin W. Andrushko ◽

Jacob Tober ◽

...

Keyword(s):

Movement Velocity ◽

Neuromuscular Activation ◽

And Performance

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Isolation and characterization of ciliary neurotrophic factor from rabbit sciatic nerves.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(19)38979-3 ◽

1990 ◽

Vol 265 (15) ◽

pp. 8942-8947

Author(s):

L F Lin ◽

L G Armes ◽

A Sommer ◽

D J Smith ◽

F Collins

Keyword(s):

Neurotrophic Factor ◽

Ciliary Neurotrophic Factor ◽

Isolation And Characterization ◽

Sciatic Nerves

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Chronic enhancement of neuromuscular activity increases acetylcholinesterase gene expression in skeletal muscle

AJP Cell Physiology ◽

10.1152/ajpcell.1995.269.4.c856 ◽

1995 ◽

Vol 269 (4) ◽

pp. C856-C862 ◽

Cited By ~ 33

Author(s):

H. Sveistrup ◽

R. Y. Chan ◽

B. J. Jasmin

Keyword(s):

Ache Activity ◽

Wheel Running ◽

Compensatory Hypertrophy ◽

Molecular Forms ◽

Plantaris Muscle ◽

Neuromuscular Activation ◽

Neuromuscular Activity ◽

Acetylcholinesterase Gene ◽

Voluntary Wheel

We determined levels of mRNA encoding acetylcholinesterase (AChE) in muscles of rats subjected to chronic enhancement of neuromuscular activation. After 8 wk of voluntary wheel running, extensor digitorum longus (EDL) muscles displayed a 72% increase in total AChE activity as a result of a selective threefold increase in the G4 content. Soleus muscles, on the other hand, exhibited a 30% decrease in A12 while displaying a small (33%) increase in total AChE activity. These enzymatic adaptations were paralleled by increases in the levels of AChE mRNAs in both EDL (32%; P < 0.03) and soleus (42%; P < 0.02) muscles. In addition, compensatory hypertrophy of the plantaris muscle increased total AChE activity by 75%. This change was reflected by an elevation in all AChE molecular forms with A12 (89%) and A8 (179%) showing the most prominent increases. Similar to exercise-trained muscles, hypertrophied plantaris muscles displayed an increase in AChE transcripts (25%; P < 0.04). These results indicate that increases in neuromuscular activity modulate expression of the AChE gene in vivo and suggest the involvement of pretranslational regulatory mechanisms in the adaptive response of AChE to enhanced neuromuscular activation.

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