Electroneurography of the ulnar nerve in dogs

Electroneurography as one of the electrodiagnostic techniques is used to measure the speed of action potential which is propagated down the nerve after stimulation. It gives information about normal functioning of the peripheral nerves. The aim of this study was to evaluate the applicability of a new electroneurographic technique by performing motor nerve conduction velocity measurements in the ulnar nerve with surface stimulating electrodes in healthy dogs, to correlate the obtained data by age, limb length, rectal temperature, and sex; and to compare these results with published findings utilizing needle stimulating electrodes. The study was performed in 24 clinically healthy dogs without anaesthesia. Rectal temperatures and limb lengths were measured in all individuals. There were significant correlations among several indicators (age, rectal temperature, limb length, conduction velocity, latency and duration of compound muscle action potentials). Limb length was found to have a significant effect on the duration of the compound muscle action potential from both stimulation sites (proximal/distal; r = 0.71, r = 0.68, P < 0.01), but there was no effect on the conduction velocity or amplitude of the action potentials. There was no significant difference (P > 0.05) in the measured indicators between males and females, even though females had a higher mean conduction velocity than males. These results prove that conduction velocity measurements in dogs could be performed non-invasively, without a danger of infection or haematomas or complications with anaesthesia, which is more favourable and time-saving for clinical practice, and more comfortable for patients.

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Activity-Dependent Modulation of Axonal Excitability in Unmyelinated Peripheral Rat Nerve Fibers by the 5-HT(3) Serotonin Receptor

Journal of Neurophysiology ◽

10.1152/jn.00716.2006 ◽

2006 ◽

Vol 96 (6) ◽

pp. 2963-2971 ◽

Cited By ~ 22

Author(s):

Philip M. Lang ◽

Gila Moalem-Taylor ◽

David J. Tracey ◽

Hugh Bostock ◽

Peter Grafe

Keyword(s):

Action Potential ◽

Conduction Velocity ◽

Action Potentials ◽

Serotonin Receptor ◽

Nerve Fibers ◽

Nerve Trunk ◽

Axonal Membrane ◽

Membrane Hyperpolarization ◽

Axonal Excitability ◽

Activity Dependent

Activity-dependent fluctuations in axonal excitability and changes in interspike intervals modify the conduction of trains of action potentials in unmyelinated peripheral nerve fibers. During inflammation of a nerve trunk, long stretches of axons are exposed to inflammatory mediators such as 5-hydroxytryptamine [5-HT]. In the present study, we have tested the effects of m-chlorophenylbiguanide (mCPBG), an agonist at the 5-HT(3) serotonin receptor, on activity- and potential-dependent variations in membrane threshold and conduction velocity of unmyelinated C-fiber axons of isolated rat sural nerve segments. The increase in axonal excitability during application of mCPBG was much stronger at higher frequencies of action potentials and/or during axonal membrane hyperpolarization. The effects on the postspike recovery cycle also depended on the rate of stimulation. At an action potential frequency of 1 Hz or in hyperpolarized axons, mCPBG produced a loss of superexcitability. In contrast, at 0.33 Hz, a small increase in the postspike subexcitability was observed. Similar effects on excitability changes were found when latency instead of threshold was recorded, but only at higher action potential frequencies: at 1.8 Hz, mCPBG increased conduction velocity and reduced postspike supernormality. The latter effect would increase the interspike interval if pairs of action potentials were conducted along several cm in an inflamed nerve trunk. These data indicate that activation of axonal 5-HT(3) receptors not only enhances membrane excitability but also modulates action potential trains in unmyelinated, including nociceptive, nerve fibers at high impulse rates.

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The Ionic Basis of Axonal Conduction in the Central Nervous System of Viviparus Contectus (Millet) (Gastropoda: Prosobranchia)

Journal of Experimental Biology ◽

10.1242/jeb.57.1.41 ◽

1972 ◽

Vol 57 (1) ◽

pp. 41-53

Author(s):

D. B. SATTELLE

Keyword(s):

Action Potential ◽

Conduction Velocity ◽

Action Potentials ◽

Slow Component ◽

Choline Chloride ◽

Slight Reduction ◽

Action Current ◽

Sodium Dependent ◽

Dependent Mechanism ◽

Normal Ringer

1. The compound action potential recorded from the pleural-supraintestinal connective of Viviparus contectus consists of a large, slow component with an average conduction velocity of about 0.02 m/sec (at 23° C) and a faster component with a conduction velocity of 0.10 m/sec (at 23° C) for the fastest fibres. 2. Both fast and slow action potentials are rapidly abolished by the substitution of tris chloride and choline chloride for the sodium salts of normal Ringer. Tetrodotoxin, applied at 10-5M rapidly abolishes action potentials in all fibres. It is, therefore, concluded that a largely sodium-dependent mechanism of spike generation operates in all axons of the connective. 3. Lithium ions effectively substitute for sodium ions in maintaining the fast action potentials for extended periods, whereas tetraethylammonium ions do not. 4. When the calcium chloride of normal Ringer is replaced by sucrose, magnesium chloride or barium chloride, conduction of fast action potentials is maintained. A small increase in the sensitivity of all axons to tetrodotoxin is observed in calcium-free Ringer; a slight reduction in the spike amplitude of fast action potentials follows the application of manganous ions at 5 mM/l in normal Ringer. It is concluded that any possible contribution of calcium to the generation of the action current of the fast action potential is very small compared to that of sodium. 5. All axons of the connective function for extended periods in sodium-free (dextran) Ringer. Under these conditions, tetrodotoxin blocks conduction in all fibres at concentrations of 10-6M, suggesting that function in dextran Ringer is maintained by a sodium-dependent mechanism.

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Conduction Velocity of Muscle Action Potential of Knee Extensor Muscle During Evoked and Voluntary Contractions After Exhaustive Leg Pedaling Exercise

Frontiers in Physiology ◽

10.3389/fphys.2020.00546 ◽

2020 ◽

Vol 11 ◽

Author(s):

Kohei Watanabe ◽

Taiki Sakai ◽

Shosaku Kato ◽

Natsuka Hashizume ◽

Naoki Horii ◽

...

Keyword(s):

Action Potential ◽

Conduction Velocity ◽

Knee Extensor ◽

Extensor Muscle ◽

Muscle Action ◽

Muscle Action Potential ◽

Voluntary Contractions

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P89: Do higher proximal ulnar nerve compound muscle action potentials result from higher conduction velocities of axons mediating the second of its two negative peaks?

Clinical Neurophysiology ◽

10.1016/s1388-2457(14)50240-4 ◽

2014 ◽

Vol 125 ◽

pp. S72

Author(s):

S. Gak ◽

J. Zidar

Keyword(s):

Ulnar Nerve ◽

Action Potentials ◽

Muscle Action ◽

Compound Muscle Action Potentials ◽

Conduction Velocities

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Portable conduction velocity experiments using earthworms for the college and high school neuroscience teaching laboratory

AJP Advances in Physiology Education ◽

10.1152/advan.00088.2013 ◽

2014 ◽

Vol 38 (1) ◽

pp. 62-70 ◽

Cited By ~ 12

Author(s):

Kyle M. Shannon ◽

Gregory J. Gage ◽

Aleksandra Jankovic ◽

W. Jeffrey Wilson ◽

Timothy C. Marzullo

Keyword(s):

High School ◽

Conduction Velocity ◽

Classroom Environment ◽

Action Potentials ◽

Low Cost ◽

Electrode Placement ◽

Giant Fiber ◽

Velocity Measurements ◽

Single Action ◽

Tactile Stimuli

The earthworm is ideal for studying action potential conduction velocity in a classroom setting, as its simple linear anatomy allows easy axon length measurements and the worm's sparse coding allows single action potentials to be easily identified. The earthworm has two giant fiber systems (lateral and medial) with different conduction velocities that can be easily measured by manipulating electrode placement and the tactile stimulus. Here, we present a portable and robust experimental setup that allows students to perform conduction velocity measurements within a 30-min to 1-h laboratory session. Our improvement over this well-known preparation is the combination of behaviorally relevant tactile stimuli (avoiding electrical stimulation) with the invention of minimal, low-cost, and portable equipment. We tested these experiments during workshops in both a high school and college classroom environment and found positive learning outcomes when we compared pre- and posttests taken by the students.

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The Promising Application of a New Ulnar Nerve Compound Muscle Action Potential Measurement Montage in Amyotrophic Lateral Sclerosis

10.21203/rs.3.rs-1185620/v1 ◽

2022 ◽

Author(s):

Yixuan Zhang ◽

Jingyue Ma ◽

Shuo Zhang ◽

Zhou Yu ◽

Dongsheng Fan

Keyword(s):

Amyotrophic Lateral Sclerosis ◽

Action Potential ◽

Ulnar Nerve ◽

Nerve Conduction ◽

Compound Muscle Action Potential ◽

Muscle Action ◽

Potential Measurement ◽

Muscle Action Potential ◽

Als Patients ◽

Lateral Sclerosis

Abstract Objective Detecting peripheral nerve damage by electrophysiology examination accurately and sensitively is important for the follow-up evaluation of amyotrophic lateral sclerosis(ALS). In this study, we applied a new proximal E2 electrode in the ulnar motor nerve conduction study with E1 on abductor digiti minimi(ADM), and investigated its effect on the compound muscle action potential(CMAP) of the ulnar nerve. Methods We included 64 ALS patients and 64 age- and sex- matched controls. Patients characteristics were collected for phenotype, symptom duration and site of onset. The revised ALS Functional Rating Scale(ALSFRS-R) was evaluated at the time of administration to assess the severity of ALS. The ulnar nerve CMAP was recorded using an E1 electrode on the muscle belly and an E2 electrode on distal tendon(traditional montage, CMAP-dE2) and proximal tendon(new montage, CMAP-pE2) respectively. Results The waveform of CMAP-pE2 was steadier presenting a uniform unilobed pattern. In the controls, there were no significant differences between the amplitudes of CMAP-dE2 and CMAP-pE2(p=0.96). In ALS patients, the amplitude of CMAP-pE2 was significantly lower than that of CMAP-dE2(p<0.01), especially for patients with ADM spontaneous activity and muscular atrophy. Using the new method, the damaged axons were more likely to be stratified into more severe decreased levels. Furthermore, the decline of CMAP-pE2 was significantly correlated with ALSFRS-R(p<0.01). Conclusions The new electrode configuration in the ulnar nerve conduction test could reflect the degree of axonal injury much more sensitively after the presence of ulnar nerve degeneration and was more suitable for the evaluation of disease progression.

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Online muscle fibre action potential conduction velocity measurements using the surface e.m.g. cross-correlation technique

Medical & Biological Engineering & Computing ◽

10.1007/bf02441547 ◽

1983 ◽

Vol 21 (2) ◽

pp. 239-240 ◽

Cited By ~ 13

Author(s):

H. Zorn ◽

M. Naeije

Keyword(s):

Action Potential ◽

Muscle Fibre ◽

Conduction Velocity ◽

Cross Correlation ◽

Correlation Technique ◽

Velocity Measurements ◽

Cross Correlation Technique

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Optical recording of action potential initiation and propagation in mouse skeletal muscle fibers

10.1101/292391 ◽

2018 ◽

Author(s):

Q. Banks ◽

S.J.P. Pratt ◽

S.R. Iyer ◽

R.M. Lovering ◽

E.O. Hernández-Ochoa ◽

...

Keyword(s):

Skeletal Muscle ◽

Action Potential ◽

Conduction Velocity ◽

Muscle Fibers ◽

Extracellular Potassium ◽

Bipolar Electrode ◽

Muscle Action ◽

Action Potential Propagation ◽

Skeletal Muscle Fibers ◽

Muscle Action Potential

ABSTRACTIndividual skeletal muscle fibers have been used to examine a wide variety of cellular functions and pathologies. Among other parameters, skeletal muscle action potential propagation has been measured to assess the integrity and function of skeletal muscle. In this paper, we utilize Di-8-ANEPPS, a potentiometric dye and mag-fluo-4, a low-affinity intracellular calcium indicator to non-invasively and reliably measure action potential conduction velocity in skeletal muscle. We used an extracellular bipolar electrode to generate an electric field that will initiate an action potential at one end of the fiber or the other. Using enzymatically dissociated flexor digitorum brevis (FDB) fibers, we demonstrate the strength and applicability of this technique. Using high-speed line scans, we estimate the conduction velocity to be approximately 0.4 m/s. In addition to measuring the conduction velocity, we can also measure the passive electrotonic potentials elicited by pulses by either applying tetrodotoxin (TTX) or reducing the bath sodium levels. We applied these methodologies to FDB fibers under elevated extracellular potassium conditions, and found that the conduction velocity is significantly reduced compared to our control concentration. Lastly, we have constructed a circuit model of a skeletal muscle in order to predict passive polarization of the fiber by the field stimuli. Our predictions from the model fiber closely resemble the recordings acquired from in vitro assays. With these techniques, we can examine how many different pathologies and mutations affect skeletal muscle action potential propagation. Our work demonstrates the utility of using Di-8-ANEPPS or mag-fluo-4 to non-invasively measure action potential conduction velocity.

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