Muscle damage slows oxygen uptake kinetics during moderate-intensity exercise performed at high pedal rate

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dissociated time course recovery between rate of force development and peak torque after eccentric exercise

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Exercise reduces angiotensin II responses in rat femoral veins

The control of blood flow during exercise involves different mechanisms, one of which is the activation of the renin-angiotensin system, which contributes to exercise-induced blood flow redistribution. Moreover, although angiotensin II (Ang II) is considered a potent venoconstrictor agonist, little is known about its effects on the venous bed during exercise. Therefore, the present study aimed to assess the Ang II responses in thefemoral vein taken from sedentary and trained rats at rest or subjected to a single bout of exercise immediately before organ bath experiments. Isolated preparations of femoral veins taken from resting-sedentary, exercised-sedentary, resting-trained and exercised-trained animals were studied in an organ bath. In parallel, the mRNA expression of prepro-endothelin-1 (ppET-1), as well as the ETA and ETB receptors, was quantified by real-time PCR in this tissue. The results show that, in the presence of L-NAME, Ang II responses in resting-sedentary animals were higher compared to the other groups. However, this difference disappeared after co-treatment with indomethacin, BQ-123 or BQ-788. Moreover, exercise reduced ppET-1 mRNA expression. These reductions in mRNA expression were more evident in resting-trained animals. In conclusion, either acute or repeated exercise adapts the rat femoral veins, thereby reducing the Ang II responses. This adaptation is masked by the action of locally produced nitric oxide and involves, at least partially, the ETB- mediated release of vasodilator prostanoids. Reductions in endothelin-1 production may also be involved in these exercise-induced modifications of Ang II responses in the femoral vein.

Exercise increases the angiotensin II effects in isolated portal vein of trained rats

Training in rats adapts the portal vein to respond vigorously to sympathetic stimuli even when the animal is re-exposed to exercise. Moreover, changes in the exercise-induced effects of angiotensin II, a potent venoconstrictor agonist, in venous beds remain to be investigated. Therefore, the present study aimed to assess the effects of angiotensin II in the portal vein and vena cava from sedentary and trained rats at rest or submitted to an exercise session immediately before organ bath experiments. We found that training or exposure of sedentary animals to a single bout of running exercise does not significantly change the responses of the rat portal vein to angiotensin II. However, the exposure of trained animals to a single bout of running exercise enhanced the response of the rat portal vein to angiotensin II. This enhancement appeared to be territory-specific because it was not observed in the vena cava. Moreover, it was not observed inendothelium-disrupted preparations and in preparations treated with Nω-nitro-l-arginine methyl esterhydrochloride, indomethacin, BQ-123 or BQ-788. These data indicate that training causes adaptations in the rat portal vein that respond vigorously to angiotensin II even upon re-exposure to exercise. This increased response to angiotensin II requires an enhancement of the vasocontractile influence of endothelin beyond the influence of nitric oxide and vasodilator prostanoids.

Aorticopulmonary septal defect in a dog: case report

Na avaliação da dispneia pós-exercício em uma cadela de 10 meses de idade, não castrada e sem raça definida, foi detectado sopro sistólico leve grau II/VI. A comunicação entre a aorta ascendente e o tronco pulmonar, observada pela presença de fluxo contínuo logo abaixo das valvas semilunares, à ecoDopplercardiografia, foi confirmada pela cirurgia. Após o procedimento cirúrgico, a cadela apresentou boa condição clínica e ausência de dispneia mesmo ao exercício. Ressalta-se a importância do diagnóstico precoce e preciso para o sucesso terapêutico. Este é o primeiro relato brasileiro dessa rara doença e a única cirurgia, bem sucedida, descrita na literatura veterinária consultada.

EFFECTS of CREATINE SUPPLEMENTATION DURING RESISTANCE TRAINING on MYOSIN HEAVY CHAIN (MHC) EXPRESSION IN RAT SKELETAL MUSCLE FIBERS

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análise de parâmetros de força e resistência dos músculos eretores da espinha lombar durante a realização de exercício isométrico em diferentes níveis de esforço

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Stress biomarkers in rats submitted to swimming and treadmill running exercises

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ventricular Systolic Reserve in Asymptomatic Children Previously Treated With Low Doses of Anthracyclines

Doppler echocardiography has been used for the diagnosis of anthracycline-induced cardiotoxicity. However, few data are available that include asymptomatic children previously treated with a low cumulative dose of this drug and therefore have a low risk of cardiac dysfunction. The aim of this study was to evaluate after-exercise cardiac function in asymptomatic children previously treated with a low cumulative dose of anthracycline and no clinical or laboratory evidence of cardiotoxicity. Doppler echocardiography was performed before and immediately after physical exercise in 29 children aged 5 to 17 years (anthracycline [ADRIA] group). All had finished cancer treatment with anthracycline derivatives for ≥1 year (cumulative dose 100 mg/m2). Results were compared with those from age- and gender-matched healthy children (control group; n = 26) using the Mann-Whitney rank test. Exercise-induced cardiac function changes within groups were analyzed using Wilcoxon's signed-rank test. Exercise induced significant increases in left ventricular systolic function indexes in both groups. However, the ADRIA group had significantly lower changes in left ventricular ejection fraction (ADRIA group 0.71 ± 0.02 vs 0.80 ± 0.04 and control group 0.71 ± 0.02 vs 0.89 ± 0.05, p = 0.0017) and end-systolic stress-volume index (ADRIA group 4.59 ± 0.69 vs 6.4 ± 2.0 g.cm-2/ml.m-2 and control group 5.49 ± 0.98 vs 11.54 ± 2.86 g.cm-2/ml.m-2; p <0.0001), indicating decreased functional systolic reserve. In conclusion, asymptomatic children previously treated with low cumulative doses of anthracycline had decreased functional systolic reserve evidenced by exercise, suggesting a nonclinically manifested cardiotoxicity. © 2007 Elsevier Inc. All rights reserved.

Validation of the lactate minimum test as a specific aerobic evaluation protocol for table tennis players

The purpose of this study was to validate the lactate minimum test as a specific aerobic evaluation protocol for table tennis players. Using the frequency of 72 balls·min-1 for 90 sec, an exercise-induced metabolic acidosis was determined in 8 male table tennis players. The evaluation protocol began with a frequency of 40 balls·min-1 followed by an increase of 8 balls·min-1 every 3 min until exhaustion. The mean values that corresponded to the subjects' lactate minimum (Lacmin) were equal to 53.1 ± 1.5 balls·min-1 [adjusted for the time test (Lacmin_time)] and 51.6 ± 1.6 balls·min-1 [adjusted for the frequency of balls (Lacmin_Freq)], which resulted in a high correlation between the two forms of adjustment (r = 0.96 and (P = 0.01). The mean maximum lactate steady state (MLSS) was 52.6 ± 1.6 balls·min-1. Pearson's correlations between Lacmin_time vs. MLSS and Lacmin_freq vs. MLSS were statistically significant (P = 0.03 and r = 0.86, P = 0.03 and r = 0.85, respectively). These findings indicate that the Lacmin test predicts MLSS. Therefore, it is an excellent method to obtain the athletes' anaerobic threshold. Also, there is the advantage that it can be performed in 1 day in the game area. However, the Lacmin value does not depend on the Lacpeak value.

Avaliação clínica, endoscópica e citologica da hemorragia pulmonar induzida por exercício(EIPH) em cavalos da raça quarto de milha

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Estudo analítico das endoscopias das vias aéreas de equinos PSI durante o período de 1993-2003 e avaliação dos resultados de procedimentos cirúrgicos laringeanos realizados no Jockey Club de São Paulo durante o período de 1998-2003

Pós-graduação em Medicina Veterinária - FMVZ

Estudo da enzima conversora de angiotensina e da endotelina-1 como marcadores de lesão pulmonar em cavalos de trote com hemorragia pulmonar induzida por exercício em esteira de alta velocidade

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Variáveis fisiológicas e estresse oxidativo de eqüinos durante campeonato de enduro

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Metabolismo do ferro e lipoperoxidação eritrocitária em equinos puro sangue árabe sumetidos ao exercício em esteira e suplementados com vitamina E (dl-alfa-tocoferol)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)