Effect of Muscle Contraction Induced by Electrical Stimulation of the Long Head Triceps Brachii Muscle on the Scapula Position

Previous studies have suggested that activation of ATP-sensitive P2X receptors in skeletal muscle play a role in mediating the exercise pressor reflex (Li J and Sinoway LI. Am J Physiol Heart Circ Physiol 283: H2636–H2643, 2002). To determine the role ATP plays in this reflex, it is necessary to examine whether muscle interstitial ATP (ATPi) concentrations rise with muscle contraction. Accordingly, in this study, muscle contraction was evoked by electrical stimulation of the L7 and S1 ventral roots of the spinal cord in 12 decerebrate cats. Muscle ATPi was collected from microdialysis probes inserted in the muscle. ATP concentrations were determined by the HPLC method. Electrical stimulation of the ventral roots at 3 and 5 Hz increased mean arterial pressure by 13 ± 2 and 16 ± 3 mmHg ( P < 0.05), respectively, and it increased ATP concentration in contracting muscle by 150% ( P < 0.05) and 200% ( P < 0.05), respectively. ATP measured in the opposite control limb did not rise with ventral root stimulation. Section of the L7 and S1 dorsal roots did not affect the ATPi seen with 5-Hz ventral root stimulation. Finally, ventral roots stimulation sufficient to drive motor nerve fibers did not increase ATP in previously paralyzed cats. Thus ATPi is not largely released from sympathetic or motor nerves and does not require an intact afferent reflex pathway. We conclude that ATPi is due to the release of ATP from contracting skeletal muscle cells.

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Optogenetic activation of muscle contraction in vivo

10.1101/2020.07.07.192377 ◽

2020 ◽

Author(s):

Elahe Ganji ◽

C. Savio Chan ◽

Christopher W. Ward ◽

Megan L. Killian

Keyword(s):

Skeletal Muscle ◽

Electrical Stimulation ◽

Muscle Contraction ◽

Fluorescent Imaging ◽

Triceps Surae ◽

Light Activation ◽

Non Invasive ◽

Optogenetic Stimulation ◽

Stimulation Of

AbstractOptogenetics is an emerging alternative to traditional electrical stimulation to initiate action potentials in activatable cells both ex vivo and in vivo. Optogenetics has been commonly used in mammalian neurons and more recently, it has been adapted for activation of cardiomyocytes and skeletal muscle. Therefore, the aim of this study was to evaluate the stimulation feasibility and sustain isometric muscle contraction and limit decay for an extended period of time (1s), using non-invasive transdermal light activation of skeletal muscle (triceps surae) in vivo. We used inducible Cre recombination to target expression of Channelrhodopsin-2 (ChR2(H134R)-EYFP) in skeletal muscle (Acta1-Cre) in mice. Fluorescent imaging confirmed that ChR2 expression is localized in skeletal muscle and does not have specific expression in sciatic nerve branch, therefore, allowing for non-nerve mediated optical stimulation of skeletal muscle. We induced muscle contraction using transdermal exposure to blue light and selected 10Hz stimulation after controlled optimization experiments to sustain prolonged muscle contraction. Increasing the stimulation frequency from 10Hz to 40Hz increased the muscle contraction decay during prolonged 1s stimulation, highlighting frequency dependency and importance of membrane repolarization for effective light activation. Finally, we showed that optimized pulsed optogenetic stimulation of 10 Hz resulted in comparable ankle torque and contractile functionality to that of electrical stimulation. Our results demonstrate the feasibility and repeatability of non-invasive optogenetic stimulation of muscle in vivo and highlight optogenetic stimulation as a powerful tool for non-invasive in vivo direct activation of skeletal muscle.

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Ulnar nerve contribution in the innervation of the triceps brachii muscle ulnar nerve to the triceps brachii

Anatomy Journal of Africa ◽

10.4314/aja.v6i1.160438 ◽

1970 ◽

Vol 6 (1) ◽

pp. 834-839

Author(s):

DLR Silva ◽

MP Barros ◽

TGS Freire ◽

L Firmino Júnior ◽

WRB Almeida Filho ◽

...

Keyword(s):

Brachial Plexus ◽

Ulnar Nerve ◽

Terminal Branch ◽

Upper Limbs ◽

Triceps Brachii ◽

Medial Head ◽

Muscle Innervation ◽

Triceps Brachii Muscle ◽

Long Head ◽

Lateral Head

The ulnar nerve is considered the thickest terminal branch of the medial cord in the brachial plexus and most authors does not mention the possibility of this nerve emitting branches to the arm. However, some studies reported that the ulnar nerve could supply the medial head of triceps brachii muscle. The main objective in this study was identifying the presence of ulnar nerve branches in triceps brachii muscle. Sixty upper limbs of adult Brazilian corpses of both sexes were used. The estimated age was between 25 and 80 years old. Every studied piece had the nerves and their branches quantified and measured with a manual mechanic caliper. The branches were photographed and had the data registered in individual files. Were found ulnar nerve branches for all the heads of triceps brachii muscle: 1 branch (9,1%) to lateral head, 2 branches (18,1%) to long head and 8 branches (72,7%) to medial head. Thus, we can conclude that the contribution of ulnar nerve to triceps brachii muscle constitutes an important anatomical variation.Key words: Ulnar nerve; Triceps brachii muscle; Innervation.

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A Prominent Consolidation in the Tendon of the Long Head of the Triceps Brachii Muscle in the Greyhound

Anatomia Histologia Embryologia ◽

10.1111/j.1439-0264.1978.tb00497.x ◽

1978 ◽

Vol 7 (1) ◽

pp. 79-83 ◽

Cited By ~ 1

Author(s):

P. H. McCarthy

Keyword(s):

Triceps Brachii ◽

Triceps Brachii Muscle ◽

Long Head

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Effect of barodenervation on c-Fos expression in the medulla induced by static muscle contraction in cats

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1998.274.3.h901 ◽

1998 ◽

Vol 274 (3) ◽

pp. H901-H908 ◽

Cited By ~ 11

Author(s):

Jianhua Li ◽

Jeffrey T. Potts ◽

Jere H. Mitchell

Keyword(s):

Spinal Cord ◽

Electrical Stimulation ◽

Muscle Contraction ◽

Baroreceptor Reflex ◽

Reticular Nucleus ◽

Arterial Blood ◽

Ventral Roots ◽

Stimulation Of ◽

Arterial Baroreceptor Reflex ◽

Arterial Baroreceptor

A previous study has shown increased Fos-like immunoreactivity (FLI), a marker of neural activation, in the nucleus of the solitary tract (NTS) and the ventrolateral medulla (VLM) after static muscle contraction elicited by electrical stimulation of L7 and S1 ventral roots of the spinal cord in anesthetized, baroreceptor-intact cats. Because the electrically induced static muscle contraction reflexly increased arterial blood pressure, the concomitant activation of the arterial baroreceptor reflex during static muscle contraction may have resulted in some of the FLI labeling that was observed in the medulla. The purpose of this study was to determine regions in the medulla that are activated by muscle contraction in the absence of arterial baroreceptor input. Electrical stimulation of L7 and S1 ventral roots of the spinal cord was used to elicit static muscle contraction, and FLI in the medulla was determined in barointact and barodenervated cats. In barointact contraction cats, FLI was observed in the lateral reticular nucleus (LRN), NTS, lateral tegmental field (FTL), subretrofacial nucleus (SRF), and A1 region of the medulla. In barodenervated contraction cats, FLI increased in the same regions; however, the number of FLI-labeled cells in the NTS, FTL, and A1 region was significantly less than in barointact contraction animals. No significant difference in the number of FLI-labeled cells was found in the LRN and SRF between the two groups. These results clearly demonstrate that cardiovascular regions in the medulla are activated by input from afferent activity originating in skeletal muscle independently of concomitant arterial baroreceptor reflex activation.

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Inhibition of dynamic thigh muscle contraction by electrical stimulation of the posterior cruciate ligament in humans

Muscle & Nerve ◽

10.1002/mus.1172 ◽

2001 ◽

Vol 24 (11) ◽

pp. 1482-1488 ◽

Cited By ~ 11

Author(s):

Torsten Fischer-Rasmussen ◽

Michael Krogsgaard ◽

Dennis Bo Jensen ◽

Poul Dyhre-Poulsen

Keyword(s):

Electrical Stimulation ◽

Muscle Contraction ◽

Posterior Cruciate Ligament ◽

Cruciate Ligament ◽

Thigh Muscle ◽

Stimulation Of

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Proximal avulsion fracture of the long head of the triceps brachii muscle

Journal of the Belgian Society of Radiology ◽

10.5334/jbr-btr.1342 ◽

2014 ◽

Vol 97 (5) ◽

pp. 316

Author(s):

M. Vansevenant ◽

F.M. Vanhoenacker ◽

T. Wauters

Keyword(s):

Avulsion Fracture ◽

Triceps Brachii ◽

Triceps Brachii Muscle ◽

Long Head

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Interstitial K+ concentration in active muscle after myocardial infarction

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.00295.2006 ◽

2007 ◽

Vol 292 (2) ◽

pp. H808-H813 ◽

Cited By ~ 3

Author(s):

Jianhua Li ◽

Zhaohui Gao ◽

Valerie Kehoe ◽

Lawrence I. Sinoway

Keyword(s):

Myocardial Infarction ◽

Skeletal Muscle ◽

Electrical Stimulation ◽

Muscle Contraction ◽

Active Muscle ◽

Pump Activity ◽

Healthy Control ◽

Sciatic Nerves ◽

K Concentration ◽

Stimulation Of

Previous work demonstrated that Na+-K+ pump activity within skeletal muscle is attenuated in myocardial infarction (MI). This may lead to enhanced interstitial K+ concentration ([K+]o) in the muscle. We tested the hypothesis that [K+]o rises with muscle contraction and that, in rats with MI, the rate of rise in [K+]o is greater than it is in control animals. Microdialysis probes were inserted in the skeletal muscle of six healthy control and six MI rats. The ends of the probes were then attached to the K+ electrodes, and [K+]o was continuously measured. Muscle contraction was induced by electrical stimulation of the sciatic nerves for 1 min. Stimulation at 1 and 3 Hz increased muscle [K+]o by 14.2% and 44.7% in controls and by 22.9% and 62.8% in MI rats ( P < 0.05 vs. controls), respectively. When ouabain, an inhibitor of Na+-K+ pump, was added to the perfusate, muscle [K+]o rose significantly. This effect of ouabain was significantly attenuated in MI animals. In conclusion, when compared with that in control animals, an increase of [K+]o in exercising muscle is augmented in MI rats, likely due to an attenuation of Na+-K+ pump activity.

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AXILLARY NERVE SUPPLYING MOTOR BRANCH TO LONG HEAD OF TRICEPS BRACHII MUSCLE: A CASE REPORT AND REVIEW OF LITERATURE

10.36106/ijar/7402369 ◽

2021 ◽

pp. 69-71

Author(s):

Giridhar Dasegowda ◽

Seema Shimoga Rangappa

Keyword(s):

Radial Nerve ◽

Axillary Nerve ◽

Extensive Literature ◽

Triceps Brachii ◽

Motor Branch ◽

Traumatic Injuries ◽

Clinical Observations ◽

Male Cadaver ◽

Triceps Brachii Muscle ◽

Long Head

All three heads of the triceps brachii are classically described as being innervated by the radial nerve in the textbooks. Some clinical observations of traumatic injuries of the axillary nerve with associated paralysis of the long head of triceps and cadaveric studies have suggested that the axillary nerve may innervate the long head of triceps. During routine dissection to undergraduate M.B.B.S students, we found axillary nerve giving a motor branch to long head of triceps brachii on right side, in an adult male cadaver aged about 60 years. We conducted extensive literature search to analyse the previous studies reporting such variations and the studies conducted on the radial nerve or triceps brachii innervation pattern. This variation is clinically important for surgeons, orthopedicians and anaesthetist while performing surgeries and pain management therapies on the upper limb.

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Cobalt injections into the pedunculopontine nuclei attenuate the reflex diaphragmatic responses to muscle contraction in rats

Journal of Applied Physiology ◽

10.1152/japplphysiol.00652.2003 ◽

2004 ◽

Vol 96 (1) ◽

pp. 301-307 ◽

Cited By ~ 6

Author(s):

Edward D. Plowey ◽

Tony G. Waldrop

Keyword(s):

Electrical Stimulation ◽

Muscle Contraction ◽

Potential Role ◽

Respiratory Activity ◽

Tibial Nerve ◽

Muscular Activity ◽

Cardiovascular Responses ◽

Pedunculopontine Nucleus ◽

Hindlimb Muscle ◽

Stimulation Of

Previous studies have suggested that neurons in the pedunculopontine nucleus (PPN) are activated during static muscle contraction. Furthermore, activation of the PPN, via electrical stimulation or chemical disinhibition, is associated with increases in respiratory activity observed via diaphragmatic electromyogram recordings. The present experiments address the potential for PPN involvement in the regulation of the reflex diaphragmatic responses to muscle contraction in chloralose-urethane anesthetized rats. Diaphragmatic responses to unilateral static hindlimb muscle contraction, evoked via electrical stimulation of the tibial nerve, were recorded before and subsequent to bilateral microinjections of a synaptic blockade agent (CoCl2) into the PPN. The peak reflex increases in respiratory frequency (9.0 ± 1.0 breaths/min) and minute integrated diaphragmatic electromyogram activity (14.6 ± 3.3 units/min) were attenuated after microinjection of CoCl2 into the PPN (2.6 ± 0.9 breaths/min and 4.6 ± 2.1 units/min, respectively). Consistent diaphragmatic responses were observed in the subset of animals that were barodenervated. Control experiments suggest no effects of PPN synaptic blockade on the cardiovascular responses to muscle contraction. The results are discussed in terms of a potential role for the PPN in modulation of the reflex respiratory adjustments that accompany muscular activity.

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