Effect of an isotonic rehydration sports drink and exercise on urolithiasis in rats

The objective of the present study was to evaluate the role of physical exercise as well as the influence of hydration with an isotonic sports drink on renal function in male Wistar rats. Four groups were studied over a period of 42 days: 1) control (N = 9); 2) physical exercise (Exe, N = 7); 3) isotonic drink (Drink, N = 8); 4) physical exercise + isotonic drink (Exe + Drink, N = 8). Physical exercise consisted of running on a motor-driven treadmill for 1 h/day, at 20 m/min, 5 days a week. The isotonic sports drink was a commercial solution used by athletes for rehydration after physical activity, 2 ml administered by gavage twice a day. Urine cultures were performed in all animals. Twenty-four-hour urine samples were collected in metabolic cages at the beginning and at the end of the protocol period. Urinary and plasma parameters (sodium, potassium, urea, creatinine, calcium) did not differ among groups. However, an amorphous material was observed in the bladders of animals in the Exe + Drink and Drink groups. Characterization of the material by Western blot revealed the presence of Tamm-Horsfall protein and angiotensin converting enzyme. Physical exercise and the isotonic drink did not change the plasma or urinary parameters measured. However, the isotonic drink induced the formation of intravesical matrix, suggesting a potential lithogenic risk.Universidade Federal de São Paulo (UNIFESP) Departamento de Medicina Disciplina de NefrologiaUniversidade Federal de São Paulo (UNIFESP) Departamento de Farmacologia Disciplina de Fisiologia Cardiovascular e RespiratóriaUNIFESP, Depto. de Medicina Disciplina de NefrologiaUNIFESP, Depto. de Farmacologia Disciplina de Fisiologia Cardiovascular e RespiratóriaSciEL

Exercise Attenuates Renal Dysfunction with Preservation of Myocardial Function in Chronic Kidney Disease

Previous studies have suggested that exercise improves renal and cardiac functions in patients with chronic kidney disease. the aim of this study was to evaluate the effects of long-term aerobic swimming exercise with overload on renal and cardiac function in rats with 5/6 nefrectomy (5/6Nx). Eight Wistar rats were placed into 4 groups: Control (C), Control+Exercise (E), Sedentary 5/6Nx (NxS) and 5/6Nx+Exercise (NxE). the rats were subjected to swimming exercise sessions with overload for 30 min five days per week for five weeks. Exercise reduced the effect of 5/6Nx on creatinine clearance compared to the NxS group. in addition, exercise minimized the increase in mean proteinuria compared to the NxS group (96.9 +/- 10.0 vs. 51.4 +/- 9.9 mg/24 h; p<0.05). Blood pressure was higher in the NxS and NxE groups compared to the C and E groups (216 +/- 4 and 178 +/- 3 vs. 123 +/- 2 and 124 +/- 2 mm Hg, p<0.05). in the 200 glomeruli that were evaluated, the NxS group had a higher sclerosis index than did the NxE group (16% vs. 2%, p<0.05). Echocardiography demonstrated a higher anterior wall of the left ventricle (LV) in diastole in the NxS group compared with the C, E and NxE groups. the NxS group also had a higher LV posterior wall in diastole and systole compared with the E group. the developed isometric tension in Lmax of the heart papillary muscle was lower in the NxS group compared with the C, E and NxE groups. These results suggested that exercise in 5/6Nx animals might reduce the progression of renal disease and lessen the cardiovascular impact of a reduction in renal mass.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundacao Oswaldo Ramos (FOR)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, UNIFESP EPM, Dept Med, Div Nephrol, São Paulo, BrazilUniversidade Federal de São Paulo, Cardiophysiol & Pathophysiol Lab, São Paulo, BrazilUniv São Paulo, Sch Med, Heart Inst InCor, Lab Genet & Mol Cardiol, São Paulo, BrazilUniversidade Federal de São Paulo, UNIFESP EPM, Dept Med, Div Nephrol, São Paulo, BrazilUniversidade Federal de São Paulo, Cardiophysiol & Pathophysiol Lab, São Paulo, BrazilWeb of Scienc

Previous Exercise Training Has a Beneficial Effect on Renal and Cardiovascular Function in a Model of Diabetes

Exercise training (ET) is an important intervention for chronic diseases such as diabetes mellitus (DM). However, it is not known whether previous exercise training intervention alters the physiological and medical complications of these diseases. We investigated the effects of previous ET on the progression of renal disease and cardiovascular autonomic control in rats with streptozotocin (STZ)-induced DM. Male Wistar rats were divided into five groups. All groups were followed for 15 weeks. Trained control and trained diabetic rats underwent 10 weeks of exercise training, whereas previously trained diabetic rats underwent 14 weeks of exercise training. Renal function, proteinuria, renal sympathetic nerve activity (RSNA) and the echocardiographic parameters autonomic modulation and baroreflex sensitivity (BRS) were evaluated. In the previously trained group, the urinary albumin/creatinine ratio was reduced compared with the sedentary diabetic and trained diabetic groups (p &lt; 0.05). Additionally, RSNA was normalized in the trained diabetic and previously trained diabetic animals (p &lt; 0.05). The ejection fraction was increased in the previously trained diabetic animals compared with the diabetic and trained diabetic groups (p &lt; 0.05), and the myocardial performance index was improved in the previously trained diabetic group compared with the diabetic and trained diabetic groups (p &lt; 0.05). In addition, the previously trained rats had improved heart rate variability and BRS in the tachycardic response and bradycardic response in relation to the diabetic group (p &lt; 0.05). This study demonstrates that previous ET improves the functional damage that affects DM. Additionally, our findings suggest that the development of renal and cardiac dysfunction can be minimized by 4 weeks of ET before the induction of DM by STZ.Fundacao de Amparo a Pesquisa do Estado de Sao PauloFundacao de Amparo a Pesquisa do Estado de Sao PauloConselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES)Fundacao Oswaldo RamosFundacao Oswaldo RamosCNPq-Bolsa de Produtividade em pesquisa (BPQ)CNPqBolsa de Produtividade em pesquisa (BPQ

Na+, k+ and water nephron transporters levels expression and systemic hemodinamic in pregnant normotensive or hypertensive females

Introduction: Extracelular volume expansion (ECVE) followed by decrease in vascular resistance, increase in renal plasma flow and glomerular hiperfiltration are common manifestations during normal pregnancy. Nitric oxide appears to be directly involved in the systemic alterations during pregnancy. Also, renal water and salt retention may play a role in these manifestations. Aim: The aim of this study was evaluate if the alterations in ECVE observed during normal and hypertensive pregnancy (by NO blocking) are parallel with changes in the mRNA expression levels of renal electrolytes and water transporters Methods: Wistar rats were divided in control group (C, n=5); pregnancy (P, n=5); hypertension (H, n=6) (L-NAME, 50 mg/Kg/day) and, hypertension + pregnancy (HP, n=6). The hemodynamic parameters including mean arterial pressure (MAP), heart rate (HR), stroke volume (SV), total peripheral resistance (TPR) and cardiac output (CO) were analyzed at 14th day of pregnancy. The mRNA expression levels of Na/H exchanger (NHE3), Na/K/2Cl cotransporter (BSC), K channel (ROMK2) and the aquaporin 2 (AQP2) were analyzed in the kidney tissue by Real Time-PCR technique. Results: The P group showed CO higher then C rats (P, 107±7 vs C, 84±5 ml/mim, p<0.05) without elevation in blood pressure (P, 118±2 vs C, 116±3 mmHg). The H group showed CO lower then C group (H, 44.1±2.2 vs C, 84.5±1.2; p<0.05) with significant elevation in MAP (H, 170.7±9.0 vs C, 119.4±7.4; p<0.05). Rats form HP group showed higher in TPR when compared with P group (HP, 3.5±0.4 vs P, 1.2±0.1; p<0.05) and decrease in SV (HP, 256.6±24.4 vs P, 115.5±20.5). All data of renal transporters expression are presented in arbitrary units. P rats showed decrease in ROMK2 mRNA expression (P, 0.3±0.04 vs C, 2.3±0.5, p<0.05) and increase in AQP2 (P, 3.5±0.2 vs C, 1.3±0.2, p<0.05). The H group showed significant increase in AQP2 expression when compared with C and HP groups (2.6±0.4 vs 1.3±0.2 e 1.2±0.1, respectively, p<0.05). HP showed decrease in BSC and NHE3 expression compared with P group (0.2±0.07 vs 0.8±0.2 e 1.2±0.1 vs 1.6±0.2, respectively, p<0.05). Conclusion: The hypertension induced by NO synthesis inhibition blunted systemic hemodynamic adaptations during the pregnancy. The pregnant hypertensive rats presented nephron transporters alterations (reduction in the ROMK2, BSC and NHE3 expression with increase in AQP2 expression). These data suggest that a variation on tubular transporters could mediate the hemodynamic adaptations modulate by NO during pregnancy.Introdução: Expansão do volume extracelular (VEC) seguido pela redução na resistência vascular, aumento no fluxo plasmático renal e hiperfiltração glomerular são manifestações típicas da gravidez normal. O óxido nítrico (NO) parece estar diretamente envolvido com alterações sistêmicas durante a gravidez. A retenção renal de sal e água pode desempenhar um papel significante nessas manifestações. Objetivo: Avaliar se alterações na expansão do VEC observadas durante a gravidez normal e acompanhada por hipertensão (bloqueio do NO), ocorrem em paralelo com mudanças na expressão do RNAm de transportadores renais de eletrólitos e água. Métodos: Ratas Wistar foram divididas em grupo controle (C, n=5), prenhez (P, n=5), Hipertensas (H, n=6) (L-NAME, 50mg/Kg/dia), Hipertensas + Prenhez (HP, n=6). Os parâmetros hemodinâmicos, incluindo pressão arterial média (PAM), frequência cardíaca (FC), volume sistólico (VS), resistência periférica total (RPT) e débito cardíaco (DC) foram analisados no 14º dia de prenhez. Os níveis de expressão do RNAm do trocador Na/H (NHE3), cotransportador Na/K/2Cl (BSC), canal de potássio (ROMK2) e aquaporina 2 (AQP2) foram analisados em tecido renal pela técnica de PCR em tempo real. Resultados: O grupo P apresentou DC maior que o controle (P, 107±7 vs C, 84±5 ml/mim, p<0,05) sem elevação na pressão sanguínea (P, 118±2vs C, 116±3 mmHg). O grupo H mostrou DC menor que o grupo C (H, 44,1±2,2 vs C, 84,5±1,2 ml/min, p<0,05) com significante elevação na PAM (H, 170,7±9,0 vs C, 119,4±7,4 mmHg, p<0,05). As ratas do grupo HP apresentaram aumento na RPT quando comparadas ao grupo P (HP, 3,5±0,4 vs P, 1,2±0,1 mmHg/ml/min, p<0,05) e redução no VS (HP, 256,6±24,4 vs P, 115,5±20,5 µl, p<0.05). Todos os resultados de transportadores do néfron serão apresentados em unidades arbitrárias. Ratas do grupo P apresentaram redução na expressão do RNAm do ROMK2 (P, 0,3±0,04 vs C, 2,3±0,5, p<0,05) e aumento na AQP2 (P, 3,5±0,2 vs C, 1,3±0,2, p<0,05). O grupo H mostrou aumento significante na expressão da AQP2 quando comparada aos grupos C e HP (2,6±0,4 vs 1,3±0,2 e 1,2±0,1, respectivamente, p<0,05). HP mostrou redução na expressão do BSC e NHE3 quando comparadas com o grupo P (0,2±0,07 vs 0,8±0,2 e 1,2±0,1 vs 1,6±0,2, respectivamente, p<0,05). Conclusão: A hipertensão induzida pelo bloqueio da síntese do NO impede adaptações na hemodinâmica sistêmica durante a prenhez. As ratas prenhes e hipertensas apresentaram alterações nos transportadores (redução da expressão do ROMK2, BSC e NHE3 com aumento da expressão da AQP2). Esses resultados sugerem que a variação no transporte tubular pode mediar adaptações na hemodinâmica sistêmica moduladas pelo NO durante a prenhez.TED