O efeito do intervalo da estimulação elétrica no músculo desnervado de rato

Abstract

Objective: To compare the effect of electrical stimulation (ES) applied daily and on alternate days, on the area density of the connective tissue (CT) and on the cross-sectional area (CSA) of the denervated muscle fi bers. Methods: Thirty-fi ve rats were divided into the following groups: control (C), denervated (D), denervated + daily electrical stimulation (D+DES) and denervated + alternate-day electrical stimulation (D+ES). The application of ES on the gastrocnemius was started 24 hours after nerve damage of axonotmesis type and was applied for 20 and 30 days. Cross-sections were stained with hematoxylin-eosin to measure the CSA and area density of CT. The statistical analysis consisted of the Shapiro Wilk test followed by analysis of variance (ANOVA) F (one-way) and the Tukey test (p≤ 0.05). Results: Analysis of the area density of CT showed that only the D+DES Group presented values similar to those of the C Group, for the two periods analyzed. There was no difference in CSA in the 20-day Group between the ES Groups and the D Group (p> 0.05). After 30 days, all the experimental groups reached CSA values similar to the C Group. Conclusions: The ES was ineffi cient for minimizing the muscle fi ber atrophy. However, the CT was responsive to ES, and daily applications were more benefi cial for the muscle than were alternate-day applications, thus suggesting that the interval for applying ES to denervated muscle is an important variable for CT adaptation.

Effect of electrical stimulation of the cranial tibial muscle after end-to-side neurorrhaphy of the peroneal nerve in rats

“…35 During the electrophysiological test, the rats in denervated group that showed no response to electrical stimuli, for just not having the connection between nerve and muscle, were therefore removed from the statistical analysis. Tagami et al 14 Our study is unique in that no others researches has utilized the same model to make purposeful comparisons, since most studies using electrical stimulation in denervated muscle spans seven to 52 days of observation and therefore could not possibly asess the functional evolution of animals using histological means in most cases 25,27,28,36,37 . As our duration of stimulation is relatively high and, the rats would have to undergo several sessions of ES, it was be too risky to anesthetize the rats everytime they were receiving treatment.…”

Resistance exercise recovery morphology and AQP1 expression in denervated soleus muscle of Wistar rats

“…Lesions to the sciatic nerve are characterized by pain along the nerve path or sciatica, low back pain, sensory disturbances and muscle weakness in the lower muscles (Kobayashi, Yoshizawa, & Yamada, 2011), such as the soleus muscle, which is extremely important in terms of standing and roam (Moore & Dalley, 2007). Discontinuation of neuromuscular communication leads to functional impairments because such discontinuation can result in a reduction in the cross-sectional area of muscle fibres (Junior et al 2013), atrophy (Silva-Couto et al, 2012), an increase in capillary density (Wagatsuma, Tamaki, & Ogita, 2005) and an increase in intramuscular connective tissue (Caierão, Betini, Teodori, & Minamoto, 2008).…”

Efeito da eletroestimulação no músculo desnervado de animais: revisão sistemática

“…Lima et al (29) também não observaram diferença nos valores da massa muscular e da área de secção transversa entre os grupos de intervenção e o de desnervação, resultado semelhante aos obtidos por Caierão et al (15) e Fernandes et al (5), para o uso do mesmo protocolo de intervenção.…”

“…desprovido de inervação. Caso a desnervação permaneça por um longo período de tempo, o TC substituirá os elementos contráteis do músculo, submetidos à proteólise, e atuará como inibidor da regeneração muscular após a reinervação (11,15).…”