scholarly journals PO-147 Effect of Exercise-induced Fatigue on the Electrical Activity of the External Globus Pallidus Neurons in rats

2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Hao Yu ◽  
Lijuan Hou ◽  
Jing Ma ◽  
Zhifeng Wang ◽  
Gang Zhao ◽  
...  

Objective The motor cortex (MC) stimulation-induced unitary responses of globus pallidus external segment (GPe) neurons in control and exercise induced-fatigue rats were recorded in vivo to examine the role of cortical-striatum-external globus pallidal pathway in the mechanism of central fatigue. Methods 32 Clean healthy male Wistar rats (260~300g), were randomly divided into 4 groups: control group (Control), 1-day fatigue group (1FG), 3-day fatigue group (3FG) and 7-day fatigue group (7FG). Rats were subjected to a 5-day adaptive treadmill training. Modified Bedford treadmill exercise with progressively increasing load was used to creat the exercise fatigue model. (3 levels:8.2 m/min, 15 min; 15m/min, 15 min; 20 m/min, lasting till exhaustion) The spontaneous unit activity and responses to MC stimulation of GPe neurons were recorded by the electrophysiological technique of extracellular recording of glass microelectrodes. Results The results showed that the firing frequency of high-frequency firing with pause (HFP) and low frequency firing with burst (LFB) in the GPe of 1FG was comparable with that of control group (P>0.05). However in 3FG and 7FG , the percentage of HFP neuron was significantly decreased (P<0.05), while the proportion of LFB was significantly increased (P<0.05), and the average firing rate of LFB was higher and inter spike intervals (ISI) was significantly lower than that of the control group. With 200μA electrical stimulation, the explosive discharge of GPe neurons was attenuated after fatigue in rats. The response of GPe neurons to variable frequency stimulation in exhausted model groups was stronger than that of the control group.MC-stimulation typically induced a triphasic response composed of early excitation, inhibition, and late excitation in GPe neurons. The population of neurons showing a short inhibition slightly increased in 3FG and 7FG. Conclusions 1. The results confirmed that GPe is an important nucleus of basal ganglia involved in the regulation of exercise-induced fatigue by the change of spontaneous activity. Electrical stimulation on the cortex can alter response patterns of GPe neurons in exercise-induced fatigue rats, the results confirmed that the Ctx-Str-GPe neural pathway is involved in the regulation of exercise fatigue, and the indirect pathway is over-activated.

2021 ◽  
Vol 8 ◽  
Author(s):  
Tingting Cao ◽  
Bing Xie ◽  
Siyuan Yang ◽  
Jiaqi Wang ◽  
Xiao Yang ◽  
...  

Acute urinary retention (AUR) is a troublesome urological disease, which causes various lower urinary tract symptoms. However, only few studies explored and evaluated the effective treatments to improve AUR. We aimed to find an effective approach to cure AUR through comparing the efficacy of existing classical low-frequency transcutaneous electrical nerve stimulation (TENS) and novel intravesical electrical stimulation (IVES). A total of 24 AUR female rats were divided into 3 groups as follows: control, TENS, and IVES groups. Rats in the control group had no fake stimulation. Rats in the TENS and IVES groups underwent transcutaneous or intravesical stimulation of a symmetrical biphasic rectangular current pulse with a frequency of 35 Hz, 30 min per day, for seven consecutive days. IVES significantly reduced the actin expression in the submucosal layer but increased its expression in the detrusor layer (p= 0.035,p= 0.001). The neovascularization in the submucosal layer in the IVES group was significantly increased than in the other 2 groups (p= 0.006). Low-frequency IVES performed better than TENS in terms of simultaneously relieving bladder hyperactivity, accelerating epithelial recovery, and strengthening detrusor muscle. IVES may be a promising therapeutic approach for bladder dysfunction, specifically for AUR and overactive bladder in clinical practice.


2012 ◽  
Vol 22 (03) ◽  
pp. 1250006 ◽  
Author(s):  
YUANG TANG ◽  
DOMINIQUE M. DURAND

In this study, we present a novel low-frequency electrical stimulation paradigm for mesial temporal lobe epilepsy (MTLE). The paradigm utilizes the hippocampal commissure as a unique stimulation target to simultaneously influence large portions of the bilateral hippocampal network. When applied to an acute rat model of MTLE, animals that received stimulation exhibited an 88% reduction in the signal power of the bilateral epileptiform activity relative to the control group. In addition, the stimulation entrained the hippocampal network's spontaneous epileptiform activity and disrupted its bilateral synchrony.


2007 ◽  
Vol 51 (9) ◽  
pp. 3199-3204 ◽  
Author(s):  
Xun-Zi Cai ◽  
Shi-Gui Yan ◽  
Hao-Bo Wu ◽  
Rong-Xin He ◽  
Xue-Song Dai ◽  
...  

ABSTRACT This study sought to investigate the effect of delayed pulsed-wave ultrasound with low frequency on drug release from and the antimicrobial efficacy of vancomycin-loaded acrylic bone cement in vivo and the possible mechanism of this effect. After the implantation of cement and the inoculation of Staphylococcus aureus into the bilateral hips of rabbits, ultrasound (average intensity, 300 mW/cm2; frequency, 46.5 kHz; on/off ratio, 20 min/10 min) was applied to animals in the normal ultrasound group (UG0-12) from 0 through 12 h after surgery and to those in the delayed-ultrasound group (UG12-24) from 12 through 24 h after surgery. The control group (CG) was not exposed to ultrasound. Based on vancomycin concentrations in left hip cavities at projected time intervals, the amount of time during which the local drug concentration exceeded the MIC (T >MIC) in UG12-24 was significantly prolonged compared with that in either CG or UG0-12, and the ratios between the areas under the concentration-time curves over 24 h and the MIC for UG0-12 and UG12-24 were both increased compared with that for CG. The greatest reductions in bacterial densities in both right hip aspirates and right femoral tissues at 48 h were achieved with UG12-24. Local hemorrhage in rabbits of UG0-12 during the 12-h insonation was more severe than that in rabbits of UG12-24. Of four variables, the T >MIC and the bioacoustic effect were both identified as parameters predictive of the enhancement of the antimicrobial efficacy of cement by ultrasound. Sustained concentrations above the MIC replaced early high maximum concentrations and long-term subtherapeutic release of the drug, provided that ultrasound was not applied until local hemorrhage was relieved. The enhancement of the antimicrobial efficacy of cement by ultrasound may be attributed to the prolonged T >MIC and the bioacoustic effect caused by ultrasound.


2009 ◽  
Vol 99 (6) ◽  
pp. 481-488 ◽  
Author(s):  
Michael Stratton ◽  
Thomas G. McPoil ◽  
Mark W. Cornwall ◽  
Kyle Patrick

Background: Recent research has discussed the use of low-frequency electrical stimulation to increase blood flow by eliciting muscular contraction in soft tissues. This randomized clinical trial examined the efficacy of low-frequency electrical stimulation combined with stretching exercises and foot orthoses in individuals diagnosed as having plantar fasciitis for less than 6 months. Methods: Twenty-six participants aged 18 to 65 years diagnosed as having plantar fasciitis were randomly assigned to two treatment groups: a control group receiving only stretching and orthoses and a treatment group receiving low-frequency electrical stimulation in addition to stretching and orthoses. To assess treatment response, a visual analog scale was used to determine first-step morning pain, and changes in daily activity levels were monitored by using a validated outcome measure. All of the participants were assessed before starting treatment, after 4 weeks of treatment, and 3 months after the conclusion of treatment. Results: Participants in the control and experimental groups demonstrated pain reduction and improvements in functional activity levels after 4 weeks and 3 months. Conclusions: Regardless of whether low-frequency electrical stimulation was used as an intervention, the use of plantar fascia–specific stretching and prefabricated foot orthoses provided short-term (3-month) pain relief and improvement in functional activity levels. (J Am Podiatr Med Assoc 99(6): 481–488, 2009)


2006 ◽  
Vol 291 (6) ◽  
pp. E1177-E1187 ◽  
Author(s):  
William J. Kraemer ◽  
Bradley C. Nindl ◽  
James O. Marx ◽  
Lincoln A. Gotshalk ◽  
Jill A. Bush ◽  
...  

This investigation determined the influence of acute and chronic resistance exercise on responses of growth hormone (GH) molecular variants in women. Seventy-four healthy young women (23 ± 3 yr, 167 ± 7 cm, 63.8 ± 9.3 kg, 26.3 ± 4.0% body fat) performed an acute bout of resistance exercise (6 sets of 10 repetition maximum squat). Blood samples were obtained pre- and postexercise. Resulting plasma was fractionated by molecular mass ( fraction A, >60 kDa; fraction B, 30–60 kDa; and fraction C, <30 kDa) using chromatography. Fractionated and unfractionated (UF) plasma was then assayed for GH using three different detection systems (monoclonal immunoassay, polyclonal immunoassay, and rat tibial line in vivo bioassay). Subjects were then matched and randomly placed into one of four resistance exercise training groups or a control group for 24 wk. All experimental procedures were repeated on completion of the 24-wk resistance training programs. After acute exercise, immunoassays showed consistent increases in UF GH samples and fractions B and C; increases in fraction A using immunoassay were seen only in the monoclonal assay. No consistent changes in bioactive GH were found following acute exercise. Conversely, chronic exercise induced no consistent changes in immunoassayable GH of various molecular masses, whereas, in general, bioassayable GH increased. In summary, although acute exercise increased only immunoactive GH, chronic physical training increased the biological activity of circulating GH molecular variants. Increased bioactive GH was observed across all fractions and training regimens, suggesting that chronic resistance exercise increased a spectrum of GH molecules that may be necessary for the multitude of somatogenic and metabolic actions of GH.


2018 ◽  
Vol 1 (4) ◽  
Author(s):  
Xiaoxin Wang ◽  
Ke Li ◽  
Lijuan Hou

Objective In this experiment, the Local field potential (LFPs) was observed in the substantia nigra compact and electrical activity change in corticostriatal pathway after D2DR intervention in exercise-induced fatigue rats. We analyzed the changes of DA neuron discharge and D2DR mediated corticostriatal pathway information transmission. To explore the mechanism of D2D2 mediated DA system in the information output of cortical M1 region. Methods Wistar rats were used to establish the model of exercise-induced fatigue. The rats were divided into control group (CG), 7 days fatigue group (7FG) and 24 hour recovery group (24RG). We used in vivo multichannel recording technology to record electrical activity in the M1, striatum and substantia nigra compact of rats and observed the electrophysiological changes after D2DR intervention. We also detected the expression of TH proteins in the dorsolateral striatum before and after exercise-induced fatigue by immunohistochemistry. Results 1) Compared with group CG, the expression of TH protein in the dorsolateral area of striatum was significantly decreased in group 7FG (P<0.05). 2) Compared with the CG group, the power spectral density of the θ, α and β band of the SNc was increased after seven days of exhaustion exercise(P < 0.05); After 24 hours of recovery, the PSD value decreased significantly compared with the 7FG group(P<0.05). 3)Compared with the CG group the power spectral density of alpha (7-13Hz) and beta (15-30Hz) bands in the M1 region and striatum was increased in 7FG after injection D2DR agonist(P < 0.05) . Conclusions After exercise-induced fatigue, the activity of substantia nigra was increased, and the activity of M1 and striatum was lower than that of the blank control group after the D2DR agonist  injection. As a key receptor for the DA signal system, D2DR regulates the electrical activity of the nigrostriatal DA pathway and affects the comprehensive information output of the cortex, which can be regarded as a target for exercise-induced fatigue (NSFC: 31401018,   SKXJX: 2014014, Corresponding [email protected]).


Author(s):  
Maya Ketzef ◽  
Gilad Silberberg

SummaryThe rodent external Globus Pallidus (GPe) contains two main neuronal subpopulations, prototypic and arkypallidal cells, which differ in their cellular properties. Their functional synaptic connectivity is, however, largely unknown. Here, we studied the membrane properties and synaptic inputs to these subpopulations in the mouse GPe. We obtained in vivo whole-cell recordings from identified GPe neurons and used optogenetic stimulation to dissect their afferent inputs from the striatum and subthalamic nucleus (STN). All GPe neurons received barrages of excitatory and inhibitory input during slow wave activity. The modulation of their activity was cell-type specific and shaped by their respective membrane properties and afferent inputs. Both GPe subpopulations received synaptic input from STN and striatal projection neurons (MSNs). STN and indirect pathway MSNs strongly targeted prototypic cells while direct pathway MSNs selectively inhibited arkypallidal cells. We show that GPe subtypes are differently embedded in the basal ganglia network, supporting distinct functional roles.


1999 ◽  
Vol 276 (4) ◽  
pp. E766-E773 ◽  
Author(s):  
Alena Horská ◽  
Larry J. Brant ◽  
Donald K. Ingram ◽  
Richard G. Hansford ◽  
George S. Roth ◽  
...  

We evaluated the hypothesis that long-term caloric restriction and exercise would have beneficial effects on muscle bioenergetics and performance in the rat. By themselves, each of these interventions is known to increase longevity, and bioenergetic improvements are thought to be important in this phenomenon. Accordingly, we investigated rats that underwent long-term caloric restriction and were sedentary, ad libitum-fed rats permitted to exercise by daily spontaneous wheel running (AE), and the combination of the dietary and exercise interventions (RE). Ad libitum-fed, sedentary rats comprised the control group.31P NMR spectra of the gastrocnemius muscle (GM) were collected in vivo at rest and during two periods of electrical stimulation. Neither caloric restriction nor exercise affected the ratio of phosphocreatine to ATP or pH at rest. During the first stimulation and after recovery, the RE group had a significantly smaller decline in pH than did the other groups ( P < 0.05). During the second period of stimulation, the decrease in pH was much smaller in all groups than during the first stimulation, with no differences observed among the groups. The combination of caloric restriction and exercise resulted in a significant attenuation in the decline in developed force during the second period of stimulation ( P < 0.05). A biochemical correlate of this was a significantly higher concentration of citrate synthase in the GM samples from the RE rats (32.7 ± 5.4 μmol ⋅ min−1 ⋅ g−1) compared with the AE rats (17.6 ± 5.7 μmol ⋅ min−1 ⋅ g−1; P < 0.05). Our experiments thus demonstrated a synergistic effect of long-term caloric restriction and free exercise on muscle bioenergetics during electrical stimulation.


1999 ◽  
Vol 87 (5) ◽  
pp. 1678-1683 ◽  
Author(s):  
S. Brooke Bramlett ◽  
Jun Zhou ◽  
Ruth B. S. Harris ◽  
Stephen L. Hendry ◽  
Trudy L. Witt ◽  
...  

We investigated the effect of a single bout of exercise on leptin mRNA levels in rat white adipose tissue. Male Sprague-Dawley rats were randomly assigned to an exercise or control group. Acute exercise was performed on a rodent treadmill and was carried out to exhaustion, lasting an average of 85.5 ± 1.5 min. At the end of exercise, soleus muscle and liver glycogen were reduced by 88% ( P < 0.001). Acutely exercised animals had lower ( P< 0.05) leptin mRNA levels in retroperitoneal but not epididymal fat, and this was independent of fat pad weight. To test the hypothesis that β3-adrenergic-receptor stimulation was involved in the downregulation of leptin mRNA in retroperitoneal fat, a second experiment was performed in which rats were randomized into one of four groups: control, control + β3-antagonist, exercise, and exercise + β3-antagonist. A highly selective β3-antagonist (SR-59230A) or vehicle was given by gavage 30 min before exercise or control experiment. Exercise consisted of 55 min of treadmill running, sufficient to reduce liver and muscle glycogen by 70 and 80%, respectively (both P < 0.0001). Again, acute exercise reduced leptin mRNA in retroperitoneal fat (exercise vs. control; P < 0.05), but β3-antagonism blocked this effect (exercise + β3-antagonist vs. control + β3-antagonist; P = 0.42). Unexpectedly, exercise increased serum leptin. This would be consistent with the idea that there are releasable, preformed pools of leptin within adipocytes. We conclude that β3-receptor stimulation is a mechanism by which acute exercise downregulates retroperitoneal adipose tissue leptin mRNA in vivo.


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