The objective of the present study was to propose an orthosis of light material that would be functional for the animal and that would maintain only the ankle joint immobilized. Male Wistar rats (3 to 4 months old, 250-300 g) were divided into 2 groups (N = 6): control and immobilized for 7 days. Rats were anesthetized with sodium pentobarbital (40 mg/kg weight) and the left hindlimb was immobilized with the orthoses composed of acrylic resin model, abdominal belt and lateral supports. The following analyses were performed: glycogen content of the soleus, extensor digitorum longus, white gastrocnemius, red gastrocnemius, and tibialis anterior muscles by the phenol sulfuric method, and the weight, fiber area and intramuscular connective tissue of the soleus by the planimetric system. Data were analyzed statistically by the Kolmogorov-Smirnov, Student t and Wilcoxon tests. Immobilization decreased glycogen in all muscles (P < 0.05; soleus: 31.6%, white gastrocnemius: 56.6%, red gastrocnemius: 39%, extensor digitorum longus: 41.7%, tibialis anterior: 45.2%) in addition to reducing soleus weight by 34% (P < 0.05). Furthermore, immobilization promoted reduction of the fiber area (43%, P < 0.05) and increased the connective tissue (200%, P < 0.05). The orthosis model was efficient comparing with another alternative immobilization model, like plaster casts, in promoting skeletal muscle alterations, indicating that it could be used as a new model in other studies related to muscle disuse.

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RESUMOObjetivo: Avaliar o efeito da estimulação elétrica (EE) sobre o perfil metabólico e morfométrico dos músculos do membro posterior de ratos submetidos à imobilização durante 15 dias. Método: Ratos Wistar foram divididos em 3 grupos (n=5): controle, imobilizado por 15 dias e imobilizado associado à EE por 15 dias. Foram avaliados: reserva de glicogênio (RG) dos músculos sóleo (S), extensor longo dos dedos (ELD), gastrocnêmio branco (GB), gastrocnêmio vermelho (GV) e tibial anterior (TA), além do peso do sóleo, área das fibras e tecido conjuntivo do S. A análise estatística foi feita pelos testes ANOVA e Kruskal-Wallis (p<0,05). Resultados: A imobilização promoveu alterações significativas (p<0,05) como: redução nas RG (S: 44,73%, GB: 47,82%, GV: 46,34%, ELD: 41,66%, TA: 48,38%), no peso (7,2%) e na área das fibras (35%) do S, além do aumento da densidade do tecido conjuntivo (160%). A EE promoveu aumento significativo (p<0,05) nas RG de todos os músculos imobilizados (S: 90,47%, GB: 62,5%, GV: 95,45%, ELD: 76,19%, TA: 56,25%), no peso (20,94%) e na área das fibras (19,65%) do S e também promoveu redução significativa (15,38%, p<0,05) na densidade do tecido conjuntivo. Conclusões: A EE minimizou a redução das RG, preveniu a redução da área das fibras e a proliferação do tecido conjuntivo nos músculos submetidos à imobilização.Palavras-chave: estimulação elétrica, imobilização, morfometria, metabolismo, fisioterapia. ABSTRACT Effects of Neuromuscular Electrical Stimulation on Rat Hind Limbs Immobilized for 15 Days: Metabolic and Morphometric AnalysesObjective: To evaluate the effect of electrical stimulation on the metabolic and morphometric profile of rat hind limb muscles subjected to immobilization for 15 days. Method: Wistar rats were divided into three groups (n=5): control; immobilized for 15 days; and immobilized for 15 days with electrical stimulation. The glycogen reserves of the soleus, extensor digitorum longus (EDL), white gastrocnemius (WG), red gastrocnemius (RG) and tibialis anterior (TA) muscles were evaluated, along with the weight, fibrous area and conjunctive tissue of the soleus.

Ultrasound treatment was effective in increasing the cutaneous permeation of caffeine, as evidenced by the reduction in thickness of the hypodermis and number of adipocytes.

The aim of the present study was to evaluate the effect of joint immobilization on morphometric parameters and glycogen content of soleus muscle treated with clenbuterol. Male Wistar (3-4 months old) rats were divided into 4 groups (N = 6 for each group): control, clenbuterol, immobilized, and immobilized treated with clenbuterol. Immobilization was performed with acrylic resin orthoses and 10 µg/kg body weight clenbuterol was administered subcutaneously for 7 days. The following parameters were measured the next day on soleus muscle: weight, glycogen content, cross-sectional area, and connective tissue content. The clenbuterol group showed an increase in glycogen (81.6%, 0.38 ± 0.09 vs 0.69 ± 0.06 mg/100 g; P < 0.05) without alteration in weight, cross-sectional area or connective tissue compared with the control group. The immobilized group showed a reduction in muscle weight (34.2%, 123.5 ± 5.3 vs 81.3 ± 4.6 mg; P < 0.05), glycogen content (31.6%, 0.38 ± 0.09 vs 0.26 ± 0.05 mg/100 mg; P < 0.05) and cross-sectional area (44.1%, 2574.9 ± 560.2 vs 1438.1 ± 352.2 µm 2 ; P < 0.05) and an increase in connective tissue (216.5%, 8.82 ± 3.55 vs 27.92 ± 5.36%; P < 0.05). However, the immobilized + clenbuterol group showed an increase in weight (15.9%; 81.3 ± 4.6 vs 94.2 ± 4.3 mg; P < 0.05), glycogen content (92.3%, 0.26 ± 0.05 vs 0.50 ± 0.17 mg/100 mg; P < 0.05), and cross-sectional area (19.9%, 1438.1 ± 352.2 vs 1724.8 ± 365.5 µm 2 ; P < 0.05) and a reduction in connective tissue (52.2%, 27.92 ± 5.36 vs 13.34 ± 6.86%; P < 0.05). Statistical analysis was performed using Kolmogorov-Smirnov and homoscedasticity tests. For the muscle weight and muscle glycogen content, two-way ANOVA and the Tukey test were used. For the crosssectional area and connective tissue content, Kruskal-Wallis and Tukey tests were used. This study emphasizes the importance of anabolic pharmacological protection during immobilization to minimize skeletal muscle alterations resulting from disuse.

Retinyl palmitate (RP) is widely used as a special interest ingredient in dermatological formulations to improve the elasticity of the skin and to reduce wrinkles by stimulating collagen synthesis. Nanotechnology-based drug delivery systems, such as liquid crystalline systems (LCSs), can modulate drug permeation into skin and improve the drug action. The effects of such systems on the skin, however, are not completely known. Possible undesirable effects of these formulations on the skin can be detected and interpreted by histopathology and histomorphometry. The objective of this study was to perform a rheological characterization to evaluate the safety of RP used in a lamellar LCS in vitro and in vivo. LCSs containing polyether functional siloxane as a surfactant, silicon glycol copolymer as an oil phase and water at ratios of 60:10:30 and 40:30:30, with (F₁v and F₂v, respectively) and without (F₁ and F₂ respectively) RP, were investigated. The rheological characterization was performed using steady shear rate sweep tests and dynamic frequency sweep tests carried out for up to 30 days for various storage temperature conditions (25 ± 2 °C, 37 ± 2 °C and 5 ± 2 °C). Cytotoxic effects were evaluated using J-774 mouse macrophages as a cellular model system. The in vivo tests were conducted on rabbits that had areas of skin treated as follows for 15 days: C (Control); F₁; F₁v; F₂; and F₂v. Histomorphometric and histopathological techniques were used to estimate the thicknesses of the epidermis and stratum corneum and the numbers of fibroblasts and leukocytes in the papillary dermis. Mean values were compared by ANOVA, followed by the Tukey test (p < 0.05). The steady shear rate sweep and dynamic frequency sweep tests confirmed the high viscosity of the LCS and the typical pseudo-plastic characteristic of the lamellar system. The RP-unloaded LCS and the RP-loaded LCS did not produce cytotoxicity, nor did they provoke significant thickening of the epidermis and stratum corneum. The number of leukocytes in the treated areas did not change; however, the number of fibroblasts in the area treated with F₁v was higher than in the areas treated with the control and F₂. The histological analyses demonstrated that none of the formulations irritated the skin and that formulation F₁v significantly increased the number of fibroblasts in the dermis, which could result in an increase in the production of collagen.

A proposta deste trabalho foi avaliar o músculo sóleo (S) de ratos submetidos à imobilização articular por sete dias, associado ou não ao tratamento com metformina (MET, 1,4mg.ml -1 ) por meio de análises morfométricas. Ratos adultos Wistar (n = 5) foram divididos nos grupos: controle (C), imobilizado em posição neutra do tornozelo (I), tratado com metformina (M), imobilizado tratado com metformina (I + MET). Foram avaliadas a área das fibras, a densidade de área do tecido conjuntivo intramuscular e a massa muscular do S. A análise estatística foi realizada pelo teste de normalidade, ANOVA e de Tukey (p < 0,05). A imobilização reduziu o peso muscular (mg) do S (34%). No grupo M não houve alteração significativa do peso muscular quando comparado com o grupo C. Já no grupo I + MET foi observado aumento do peso muscular em 29,6% quando comparado com o grupo I. O tratamento com metformina não alterou a área da fibra muscular quando comparado com grupo C. Já no grupo I, houve redução de 44% na área da fibra. Com relação ao grupo I + MET, houve aumento de 22% quando comparado com o grupo I. Por outro lado, ao compararmos o grupo C com o grupo I + MET, houve redução de 31%. Ao avaliar a densidade de área do tecido conjuntivo, observou-se que o grupo I apresentou elevação de 216% quando comparado com o grupo C. No grupo I + MET, houve redução de 67% comparado com o grupo I. O tratamento com metformina em músculos submetidos à imobilização minimizou a redução da área das fibras do S, bem como o aumento do tecido conjuntivo. Esses resultados sugerem que a metformina pode favorecer recuperação mais rápida na fase pós-imobilização.Palavras-chave: atrofia, desuso, metformina, reabilitação.. ABSTRACTThe aim of this study was to evaluate the effect of metformin treatment on the muscle mass, fibers area and connective tissue area density in soleus (S) muscle under articular immobilization. Methods and Results: Male Wistar rats (250-300g) were divided in 4 groups (n=5): control, treated with metformin, immobilized and immobilized treated with metformin. Immobilization was performed by acrylic resin orthoses on the left hindlimb keeping the ankle in neutral position during 7 days. The animals were euthanatized and the S muscle was dissected and weighed. Samples of its ventral portion were treated for inclusion in paraffin and stained in Hematoxylin-Eosin (H:E). The results were obtained through analyses of the muscular fiber area (images analyzed -Image Pró-plus 4,0), as well as of intramuscular connective tissue by means of planimetry. The statistical analysis was performed by normality test followed by ANOVA and Tukey (p<0.05). Hindlimb immobilization during 7 days promoted significant reduction (p<0.05) of 35% in the muscular mass; 44% (p<0.05) in the fiber area and increase of 216% (p<0.05) in the intramuscular connective tissue. The metformin in immobilized group promoted significant alterations (p<0.05) in the muscular mass. In addiction, it was observed significant increase (p<0.05) of 29.6% in the fibers area and signific...

Greater interference of the laser-treatment procedure was noted with 7 days of stimulation, and the occlusive dressing did not alter its biostimulatory effects.