Types Of Electrical Stimulation Research Articles

Development of Ocular Muscle Stimulation Systems and Optimization of Electrical Stimulus Parameters for Paralytic Strabismus Treatment.

Paralysis of the extraocular muscles can lead to complications such as strabismus, diplopia, and loss of stereopsis. Current surgical treatments aim to mitigate these issues by resecting the paralyzed muscle or transposing the other recti muscles to the paralyzed muscle, but they do not fully improve the patient's quality of life. Electrical stimulation shows promise, while requiring further in vivo experiments and research on various stimulation parameters. In this study, we conducted experiments on rabbits to stimulate the superior rectus (SR) muscles using different parameters and stimulation waveforms. To provide various types of electrical stimulation, we developed the ocular muscle stimulation systems capable of both current controlled stimulation (CCS) and high-frequency stimulation (HFS), along with the chip that enables energy-efficient and safe switched-capacitor stimulation (SCS). We also developed electrodes for easy implantation and employed safe and efficient stimulation methods including CCS, SCS, and HFS. The in vivo animal experiments on normal and paralyzed SR muscles of rabbits showed that eyeball abduction angles were proportional to the current and pulse width of the stimulation. With the decaying exponential stimuli of the SCS system, eyeball abductions were 2.58× and 5.65× larger for normal and paralyzed muscles, respectively, compared to the rectangular stimulus of CCS. HFS achieved 0.92× and 0.26× abduction for normal and paralyzed muscles, respectively, with half energy compared to CCS. In addition, the continuous changes in eyeball abduction angle in response to varying stimulation intensity over time were observed.

Electrical Stimulation for Children with Cerebral Palsy: A Meta-analysis for Randomized Controlled Trials.

Different types of electrical stimulation (ES) showed diverse effects on children with cerebral palsy (CP). Previous studies reported inconsistent results for effects of ES on children with CP. The present study aimed to conduct a meta-analysis to summarize these diverse results. We searched for studies exploring effects of ES on children with CP in databases (PubMed and Web of Science) from their inception until December 2022. Standard mean differences (SMDs) and 95% confidence intervals (CIs) were computed using STATA 12.0 software. The meta-analysis included 19 randomized controlled trials (including 265 CP patients in test group and 263 CP patients in corresponding control group). The study showed an increased improvement in gross motor function, walking speed, step length, and daily living activities in ES group compared with corresponding control group with random effects models (gross motor function: SMD = 2.04, 95% CI = 1.43-2.65; walking speed: SMD = 3.71, 95% CI = 1.49-5.92; step length: SMD = 1.89, 95% CI = 0.65-3.13; daily living activities: SMD = 5.18, 95% CI = 3.04-7.31), whereas the study showed no significant difference in change of muscle strength between ES group and the corresponding control group with a random effects model (SMD = 0.42, 95% CI = -0.12 to 0.97). The study demonstrated that ES might be used as therapy to improve gross motor function, gait, and daily living activities in children with CP.

Arthralgia: a map of Cochrane evidence relevant to rehabilitation for people with post COVID-19 condition.

Rehabilitation focuses on impairments, activity limitations and participation restrictions being informed by the underlying health condition. In the current absence of direct "evidence on" rehabilitation interventions for people with post COVID-19 condition (PCC), we can search and synthesize the indirect "evidence relevant to" coming from interventions effective on the symptoms of PCC in other health conditions. The World Health Organization (WHO) required this information to inform expert teams and provide specific recommendations in its Guidelines. With this overview of reviews with mapping we aimed to synthesize the Cochrane evidence relevant to rehabilitation for arthralgia due to PCC in a map. We searched the last five years' Cochrane Systematic Review (CSRs) using the terms "arthralgia," "joint pain," and "rehabilitation" and their synonyms in the Cochrane Library. We extracted and summarized all the available evidence using a map. We grouped the included CSRs for health conditions and interventions, indicating the effect and the quality of evidence. We found 200 CSRs published between 2016 and 2021, and included 11 in this overview. They provided data from 7 health conditions, with osteoarthritis (5 studies) being the most studied. Effective rehabilitation interventions included exercise training, transcranial magnetic stimulation, different types of electrical stimulation and Tai chi. The overall quality of evidence was mainly low to very low, and moderate in a few cases. These results provided the requested information to the WHO and served as the basis for one recommendation on treatments for arthralgia due to PCC in the current Guidelines for clinical practice. These results should be interpreted as a first step of indirect evidence able to generate helpful hypotheses for future research.

Effects on venous flow of transcutaneous electrical stimulation, neuromuscular stimulation, and sham stimulation on soleus muscle: A randomized crossover study in healthy subjects.

Background:Activation of venous flow has been shown with different types of electrical stimulation. The aim of this study is to compare the hemodynamic effects of transcutaneous electrical nerve stimulation (TENS), neuromuscular electrical stimulation (NMES), and sham stimulation on healthy young people.Methods:This randomized crossover study was conducted during June 2018 in the Faculty of Physical Therapy of A Coruña (Spain). Twenty-four university students (50% male) received in a randomized order 5 Hz-TENS, NMES, and sham stimulation on soleus muscle. Flow volume (FV) and peak velocity (PV) from popliteal vein were recorded via Doppler ultrasound, and relative changes from baseline were determined. Discomfort among the 3 stimulations was also compared.Results:The differences among the 3 stimulations were assessed using the ANOVA for repeated measured, the Friedman test and the Kendall tau test, according to the type of measurement to be compared. FV (mL/min) and PV (cm/s) increased significantly after NMES (percentual increase 37.2 ± 62.0%, P = .002; 264.4 ± 152.2%, P < .001, respectively) and TENS (226.2 ± 190.3%, P < .001; 202.7 ± 144.6%, P < .001, respectively). These percentual changes from basal level in hemodynamics were statistically different to those after placebo, which was ineffective enhancing hemodynamics. The improvements in FV were statistically higher with TENS than with NMES (P < .001), but there was no statistical difference in PV (P = .531). Despite NMES was applied at a significantly lower amplitude than TENS (P < .001), NMES protocol was the worst tolerated, though the differences in discomfort were not statistically significant.Conclusion:Both active electrical protocols but not sham stimulation increased hemodynamics in healthy people. TENS obtained higher flow volume increase from baseline than NMES, considered globally at not only in its on-time.

Using Constrained Square-Root Cubature Kalman Filter for Quantifying the Severity of Epileptic Activities in Mice.

(1) Background: Quantification of severity of epileptic activities, especially during electrical stimulation, is an unmet need for seizure control and evaluation of therapeutic efficacy. In this study, a parameter ratio derived from constrained square-root cubature Kalman filter (CSCKF) was formulated to quantify the excitability of local neural network and compared with three commonly used indicators, namely, band power, Teager energy operator, and sample entropy, to objectively determine their effectiveness in quantifying the severity of epileptiform discharges in mice. (2) Methods: A set of one normal and four types of epileptic EEGs was generated by a mathematical model. EEG data of epileptiform discharges during two types of electrical stimulation were recorded in 20 mice. Then, EEG segments of 5 s in length before, during and after the real and sham stimulation were collected. Both simulated and experimental data were used to compare the consistency and differences among the performance indicators. (3) Results: For the experimental data, the results of the four indicators were inconsistent during both types of electrical stimulation, although there was a trend that seizure severity changed with the indicators. For the simulated data, when the simulated EEG segments were used, the results of all four indicators were similar; however, this trend did not match the trend of excitability of the model network. In the model output which retained the DC component, except for the CSCKF parameter ratio, the results of the other three indicators were almost identical to those using the simulated EEG. For CSCKF, the parameter ratio faithfully reflected the excitability of the neural network. (4) Conclusion: For common EEG, CSCKF did not outperform other commonly used performance indicators. However, for EEG with a preserved DC component, CSCKF had the potential to quantify the excitability of the neural network and the associated severity of epileptiform discharges.

Энтеральная недостаточность в патогенезе острой кишечной непроходимости и методы ее коррекции (обзор литературы)

Enteral insufficiency syndrome in acute intestinal obstruction leads to a violation of the motor evacuation, secretory, digesting, absorbing, endocrine, immune, metabolic and barrier functions of the intestine. The accumulation of intestinal contents contributes to an increase in intracavitary pressure (compartment syndrome), violation of intramural hemocirculation, the development of interstitial edema, colonization and translocation of microbacteria. Nasointestinal intubation restores the evacuation function of the intestine, frees it from its contents, reduces pressure in the intestinal cavity, relieving microcirculatory disorders in the intestinal wall. In the future, the patient is prescribed enteral nutrition, selective intestinal decontamination and enterosorption are carried out. To restore the motor-evacuation function of the intestine, various types of electrical stimulation are successfully used. Thus, early diagnosis and timely correction of enteral insufficiency syndrome prevents the progression of multiple organ failure in acute intestinal obstruction.

Effect of different types of electrical stimulation on intracellular calcium levels in human mesenchymal stem cells and chondrocytes

Purpose: Electrostimulation (ES) is a noninvasive treatment modality used for pain relief in osteoarthritis (OA). However, the effects of ES are not restricted to peripheral nerves and impact joint tissues also. At the cellular level ES changes the membrane potential and ion fluxes through voltage gated ion channels, thus stimulating intracellular processes and regulating cell differentiation. Voltage gated calcium channels (VGCC) are one of the most important channels enabling calcium ion entry into cells, which further participate in various signaling pathways during cell proliferation, differentiation and metabolism.

Medical rehabilitation of children with hydronephrosis with concomitant neurogenic bladder dysfunction

Background. After operations on the ureter, it is important to use medical rehabilitation technologies aimed at preventing urodynamic disorders of the upper and lower urinary tract, stimulating reparative processes. In recent years, special attention has been drawn to high-intensity pulsed magnetotherapy, which has a more pronounced and long-lasting stimulating effect compared to other types of electrical stimulation.&#x0D; Aim: to substantiate the feasibility of including high-intensity pulsed magnetic therapy in the comprehensive medical rehabilitation of children with hydronephrosis and concomitant neurogenic bladder dysfunction.&#x0D; Methods. Clinical observations and special studies with the inclusion of high-intensity pulse magnetic therapy in the course of therapy were conducted in 100 children aged 4 to 15 years with hydronephrosis, a condition after surgery.&#x0D; Results. Medical rehabilitation with the inclusion of high-intensity pulsed magnetic therapy had a positive effect on the urodynamics of the urinary tract, renal blood flow, helped to stop inflammation in the renal parenchyma and restore the rhythm of urination in children with hydronephrosis and concomitant neurogenic bladder dysfunction.&#x0D; Conclusion. According to the research results, the feasibility of including high-intensity pulsed magnetic therapy in the complex of medical rehabilitation of children with hydronephrosis, concomitant neurogenic bladder dysfunction, is scientifically justified.

A Randomized Controlled Trial Comparing Electromyography-Triggered, Cyclic, and Sensory Electrical Stimulation

Abstract Date Presented 03/28/20 Stroke-induced arm weakness is a leading cause of worldwide disability. OT practitioners commonly employ this modality, but it is unclear which type of electrical stimulation works best for people with stroke-induced weakness. This study compared the efficacy of three types of electrical stimulation for people zero to six months poststroke. We found that all three types of stimulation worked equally well. Primary Author and Speaker: Stephen Page Contributing Authors: John Chae, Richard Wilson

The synergistic effect of biomimetic electrical stimulation and extracellular-matrix-mimetic nanopattern for upregulating cell activities

Endogenous bioelectric signaling and the extracellular matrix (ECM) are factors that have a great effect on the performance of cellular functions. Presenting an experimental platform to confirm the synergy effects of an electrical stimulation, which simulates endogenous bioelectricity, and nanopatterns that can be precisely fabricated in various patterns sizes makes it possible to consider those factors effectively. Herein, we have performed a comparison of cellular response to each of general electrical stimulation and biomimetic electrical stimulation (BES) and demonstrated the synergy effects of electrical stimulation and ECM-mimetic nanopatterns. BES has provided the most remarkable proliferation among different types of electrical stimulation and upregulated the behavior of cells through synergy effects with ECM-mimetic nanopatterns. Thus, it is believed that using the synergy effects of BES and ECM-like nanopatterns has broad applications in the biomedical field, such as cell culture with electrical stimulation, induction of cell growth, tissue repair, etc.

Immediate and long-term results of physiotherapeutic treatment of patients with chronic constipation in abnormal development of the colon

Background. Currently, the issue of effective conservative treatment of constipation in cases of colon developmental abnormalities remains open.&#x0D; Aim: to study the immediate and long-term results of the treatment of chronic constipation in case of colon development abnormalities, through individualization of the physiotherapeutic methods used, depending on the type of pathology.&#x0D; Methods. The article presents the experience of treatment in the Department of Internal Medicine of the Lugansk Republican Clinical Hospital, from 2013 to the present, of 389 patients with chronic constipation in colon developmental abnormalities. We used types of electrical stimulation, different in the method of applying electrodes and the stimulating current parameters. In the work, we used the serial apparatus Endoton 01-B. We evaluated the immediate and long-term results of treatment in the period from 6 months to 3 years.&#x0D; Results. After 34 courses of rectal electrostimulation of patients with compensated and subcompensated forms of the disease, for 67 months, 346 (88.95%) patients had regular independent defecation with an interval of 2436 hours. The remaining 43 (11.05%) patients with subcompensated and decompensated forms of the disease received 56 courses of rectal electrical stimulation during the year. A persistent positive effect was obtained, namely independent defecation with an interval of 3648 hours.&#x0D; Conclusion. Rectal electrical stimulation for this pathology is considered the method of choice. The functional immediate and long-term results of rehabilitation of patients confirmed the correctness of the approach chosen.

Medical rehabilitation of children with hydronephrosis with concomitant neurogenic bladder dysfunction

The article presents modern technologies for medical rehabilitation of children with hydronephrosis, with concomitant neurogenic bladder dysfunction. The problem of medical rehabilitation of children with hydronephrosis is due to the high frequency of occurrence; the possibility of developing chronic kidney disease; early disability. After operations on the ureter, it is important to use medical rehabilitation technologies aimed at preventing urodynamic disorders in the upper and lower urinary tract, stimulating reparative processes. Among the medical rehabilitation technologies, in recent years, special attention has been drawn to high-intensity pulsed magnetotherapy, which has a more pronounced and lasting stimulating eff ect compared to various types of electrical stimulation. Clinical observations and special studies were conducted in 100 children with hydronephrosis, the state after surgery, aged 4 to 15 years. According to the research results: The feasibility of including high-intensity pulsed magnetotherapy in the complex of medical rehabilitation of children with hydronephrosis, with concomitant neurogenic bladder dysfunction. Medical rehabilitation, with the inclusion of high-intensity pulsed magnetotherapy, had a positive eff ect on the urodynamics of the urinary tract, renal blood fl ow, helped to stop infl ammation in the renal parenchyma and restore the urination rhythm in children with hydronephrosis, with concomitant neurogenic bladder dysfunction.

A systematic review of lower extremity electrical stimulation for treatment of walking impairment in peripheral artery disease.

Lower extremity peripheral artery disease (PAD) induces an ischemic pain in the lower limbs and leads to walking impairment. Electrical stimulation has been used in patients with PAD, but no systematic review has been proposed to address the efficacy of the technique as a treatment for walking impairment in PAD. A systematic search was performed to identify trials focused on electrical stimulation for the treatment of walking impairment in patients with PAD in the Cochrane Central Register, PubMed, Embase, and the Web of Science. Studies were included where the primary outcomes were pain-free walking distance and/or maximal walking distance. When appropriate, eligible studies were independently assessed for quality using the Cochrane Collaboration's tool for assessing risk of bias. Five studies eligible for inclusion were identified, of which only two were randomized controlled studies. Trial heterogeneity prevented the use of the GRADE system and the implementation of a meta-analysis. Three types of electrical stimulation have been used: neuromuscular electrical stimulation (NMES, n = 3), transcutaneous electrical stimulation (n = 1), and functional electrical stimulation (n = 1). The two available randomized controlled studies reported a significant improvement in maximal walking distance (+40 m/+34% and +39 m/+35%, respectively) following a program of NMES. Owing to the low number of eligible studies, small sample size, and the risk of bias, no clear clinical indication can be drawn regarding the efficacy of electrical stimulation for the management of impaired walking function in patients with PAD. Future high-quality studies are required to define objectively the effect of electrical stimulation on walking capacity.

Effectiveness of electrical stimulation therapy in improving arm function after stroke: a systematic review and a meta-analysis of randomised controlled trials

Objective: The aim of this study is to investigate the effectiveness of electrical stimulation in arm function recovery after stroke. Methods: Data were obtained from the PubMed, Cochrane Library, Embase, and Scopus databases from their inception until 12 January 2019. Only randomized controlled trials (RCTs) reporting the effects of electrical stimulation on the recovery of arm function after stroke were selected. Results: Forty-eight RCTs with a total of 1712 patients were included in the analysis. The body function assessment, Upper-Extremity Fugl-Meyer Assessment, indicated more favorable outcomes in the electrical stimulation group than in the placebo group immediately after treatment (23 RCTs (n = 794): standard mean difference (SMD) = 0.67, 95% confidence interval (CI) = 0.51–0.84) and at follow-up (12 RCTs (n = 391): SMD = 0.66, 95% CI = 0.35–0.97). The activity assessment, Action Research Arm Test, revealed superior outcomes in the electrical stimulation group than those in the placebo group immediately after treatment (10 RCTs (n = 411): SMD = 0.70, 95% CI = 0.39–1.02) and at follow-up (8 RCTs (n = 289): SMD = 0.93, 95% CI = 0.34–1.52). Other activity assessments, including Wolf Motor Function Test, Box and Block Test, and Motor Activity Log, also revealed superior outcomes in the electrical stimulation group than those in the placebo group. Comparisons between three types of electrical stimulation (sensory, cyclic, and electromyography-triggered electrical stimulation) groups revealed no significant differences in the body function and activity. Conclusion: Electrical stimulation therapy can effectively improve the arm function in stroke patients.

Medical Rehabilitation after Hydronephrosis Surgical Treatment in Children

The article presents modern technologies of medical rehabilitation of children operated for hydronephrosis. The importance of medical rehabilitation of children with hydronephrosis is associated with high incidence, possibility of developing chronic kidney disease, and early disability of these patients. After surgery on the ureter it is important to use medical rehabilitation technologies aimed at preventing urodynamics disorders of upper and lower urinary tract, and at stimulation of regenerative processes. In recent years, particular attention has been paid to high-intensity pulsed electromagnetic field therapy, which has a more significant and long-term stimulating effect compared to various types of electrical stimulation. Clinical studies were conducted in 80 children operated for hydronephrosis, aged 3 to 15. The main group consisted of 40 children who received high-intensity pulsed magnetic therapy, and 40 children were included in the control group (without physiotherapy). Basic treatment included uroseptics and exercise therapy. Effectiveness of the method was assessed using clinical, laboratory and ultrasound data, and Doppler ultrasound of the renal blood flow. The results of the study demonstrated the rationale of including high-intensity pulsed electromagnetic field therapy in medical rehabilitation of children operated for hydronephrosis. The positive effect of high-intensity pulsed electromagnetic therapy on the urodynamics of the urinary tract (reduction in the size of renal pelvis and calyx) and renal blood flow (restoration of blood flow to the renal cortex) were revealed. This method helped to reduce inflammation in the renal parenchyma (reduction of proteinuria, leukocyturia) in children operated on for hydronephrosis. A significantly higher effectiveness of medical rehabilitation with the use of high-intensity pulsed magnetic therapy was proved (87.5%).

Measuring Neuromuscular Junction Functionality.

Neuromuscular junction (NMJ) functionality plays a pivotal role when studying diseases in which the communication between motor neuron and muscle is impaired, such as aging and amyotrophic lateral sclerosis (ALS). Here we describe an experimental protocol that can be used to measure NMJ functionality by combining two types of electrical stimulation: direct muscle membrane stimulation and the stimulation through the nerve. The comparison of the muscle response to these two different stimulations can help to define, at the functional level, potential alterations in the NMJ that lead to functional decline in muscle. Ex vivo preparations are suited to well-controlled studies. Here we describe an intensive protocol to measure several parameters of muscle and NMJ functionality for the soleus-sciatic nerve preparation and for the diaphragm-phrenic nerve preparation. The protocol lasts approximately 60 min and is conducted uninterruptedly by means of a custom-made software that measures the twitch kinetics properties, the force-frequency relationship for both muscle and nerve stimulations, and two parameters specific to NMJ functionality, i.e. neurotransmission failure and intratetanic fatigue. This methodology was used to detect damages in soleus and diaphragm muscle-nerve preparations by using SOD1G93A transgenic mouse, an experimental model of ALS that ubiquitously overexpresses the mutant antioxidant enzyme superoxide dismutase 1 (SOD1).

Clinical Application of Electrotherapeutic Modalities

The purposes of this survey study were 1) to determine the frequency of use of eight forms of electrical stimulation and ultrasound in clinical practice and 2) to determine the factors that influence how and when these forms of electrical stimulation are used. A survey questionnaire was distributed to 490 physical therapists in clinics affiliated with the academic programs of Ithaca College and Temple University. Forty-five percent (221) of the distributed surveys were returned. Descriptive statistics and chi-square calculations were used in the data analysis. Respondents frequently used two forms of pulsed current and rarely used two forms of alternating current. No form of electrical current was used as frequently as ultrasound. The frequency and type of electrical stimulation used depended on the availability of electrical stimulators and the adequacy of entry-level training in electrotherapy. The results of this study suggest the need for additional electrical stimulators in physical therapy clinics, training for physical therapists, and research in electrotherapy.

Upper-Limb Recovery After Stroke

Background and purpose. This study compared the effect of cyclic neuromuscular electrical stimulation (NMES), electromyographically (EMG)-triggered NMES, and sensory stimulation on motor impairment and activity limitations in patients with upper-limb hemiplegia. Methods. This was a multicenter, single-blind, multiarm parallel-group study of nonhospitalized hemiplegic stroke survivors within 6 months of stroke. A total of 122 individuals were randomized to receive either cyclic NMES, EMG-triggered NMES, or sensory stimulation twice every weekday in 40-minute sessions, over an 8 week-period. Patients were followed for 6 months after treatment concluded. Results. There were significant increases in the Fugl-Meyer Assessment [F(1, 111) = 92.6, P < .001], FMA Wrist and Hand [F(1, 111) = 66.7, P < .001], and modified Arm Motor Ability Test [mAMAT; time effect: F(1, 111) = 91.0, P < .001] for all 3 groups. There was no significant difference in the improvement among groups in the FMA [F(2, 384) = 0.2, P = .83], FMA Wrist and Hand [F(2, 384) = 0.4, P = .70], or the mAMAT [F(2, 379) = 1.2, P = .31]. Conclusions. All groups exhibited significant improvement of impairment and functional limitation with electrical stimulation therapy applied within 6 months of stroke. Improvements were likely a result of spontaneous recovery. There was no difference based on the type of electrical stimulation that was administered.

The Effect of TENS on Random Pattern Flap Survival in Nicotinized Rats

The adverse effects of cigarettes, due to their nicotine content, may cause important ischemic complications in flaps. Electrical stimulation increases blood flow in ischemic tissues, the level of vascular endothelial growth factor, capillary density, and angiogenesis while decreasing oxygen tension in tissues. Electrical stimulation is also known to increase survival rate in flaps. In this study, which tests the hypothesis that TENS (a type of electrical stimulation) contributes to enhancement of flap viability by eliminating the adverse effects of nicotine, 40 rats were divided into 4 groups of 10 rats. Nicotinization was achieved by subcutaneous administration of 2 mg/kg per day to the rats, other than those in the Control group, for 4 weeks. The rats in one of the nicotinized groups received 20 mA, 80 Hz TENS (TENS1 group) for 1 hour daily throughout the last week before McFarlane flaps of random pattern were made in the backs of all the rats. Another nicotinized group was subjected to TENS in a similar dose after flap elevation (TENS2 group). Flap blood flow was measured before and 48 hours after their construction, and their fluorescein perfusion was measured immediately after the flap elevation. The comparison of the survival rates of the flaps revealed that, although the blood flow in the Nicotine group was significantly lower than in the Control group, it was significantly higher in the TENS1 group than in both the Control and Nicotine groups. The proportion of the area stained with fluorescein, immediately after the elevation of flaps, was significantly reduced in the Nicotine group compared to the Control group. In the TENS1 group, however, it was greater than in the nicotine and TENS2 groups. Flap viability rates decreased significantly in the Nicotine group compared with the Control group. In the TENS2 group, however, an increase was observed compared with the Nicotine group.These findings suggest that although TENS performed before flap elevation does not contribute to flap survival, despite causing a rise in blood flow, it enhances flap survival when applied postoperatively. Given the practicality and low cost of TENS, it can be concluded that it may be possible to use it in the management of ischemic complications in flap operations in smokers.

Measuring Neuromuscular Junction Functionality in the SOD1(G93A) Animal Model of Amyotrophic Lateral Sclerosis.

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that leads to motor neuron degeneration, alteration in neuromuscular junctions (NMJs), muscle atrophy, and paralysis. To investigate the NMJ functionality in ALS we tested, in vitro, two innervated muscle types excised from SOD1G93A transgenic mice at the end-stage of the disease: the Soleus, a postural muscle almost completely paralyzed at that stage, and the diaphragm, which, on the contrary, is functional until death. To this aim we employed an experimental protocol that combined two types of electrical stimulation: the direct stimulation and the stimulation through the nerve. The technique we applied allowed us to determine the relevance of NMJ functionality separately from muscle contractile properties in SOD1G93A animal model. Functional measurements revealed that the muscle contractility of transgenic diaphragms is almost unaltered in comparison to control muscles, while transgenic Soleus muscles were severely compromised. In contrast, when stimulated via the nerve, both transgenic muscle types showed a strong decrease of the contraction force, a slowing down of the kinetic parameters, as well as alterations in the neurotransmission failure parameter. All together, these results confirm a severely impaired functionality in the SOD1G93A neuromuscular junctions.