Effects of endurance training with hypoxic stimulation induced by Co^<2+> treatment on oxygen transport system in rat skeletal muscles

本研究旨在观察耐力训练后骨骼肌毛细血管几何结构和血管生成因子表达的变化。Co ^<2 +>处理组大鼠饮用含0.01%CoCl_2的水。在第一个实验中，训练和Co ^<2 +>给药持续5周。长期服用Co ^<2 +>可显著增加血液中血红蛋白浓度，无论是否进行训练，增加幅度均约为25%。仅在膈肌中，单独的Co ^<2 +>处理显著增加了总毛细血管密度和毛细血管与纤维的比率（C：F）。给予和不给予Co ^<2 +>的两个训练组均显着增加了比目鱼肌（SOL）和跖肌（PL）的C：F。在PL中，Co ^<2 +>治疗训练组的增加显著大于非Co ^<2 +>治疗训练组。VEGF阳性毛细血管（VEGF-cap）的密度在所有检查的肌肉部分中保持不变。 ...更多信息 艾德在Co ^2+给药或运动训练后。第二个实验旨在检查治疗早期VEGF表达和毛细血管几何形状的时程变化。在Co ^<2 +>给药6天和10天后，SOL中的VEGF-cap分别显著增加了27%和65%。Co ^<2 +>染毒10天后，C：F显著增加。Co ^<2 +>训练后3、6、10 d，SOL中VEGF-cap分别显著增加69%、44%、60%，而10 d后，跖肌混合纤维部分（PLm）中VEGF-cap显著增加。在SOL中训练6天和10天后，有或没有Co ^<2 +>的训练显著增加了C：F。10天后，与Co ^<2 +>一起训练显著增加了PLm的C：F，而单独训练则没有。在条件下，目前的结果表明，Co ^<2 +>给药诱导的细胞氧敏感机制的激活通过促进VEGF的表达而促进后腿肌肉中的微血管重塑。少

This study was designed to examine the changes in the capillary geometry and expression of angiogenic growth factor in skeletal muscles after endurance training with and without chronic CoCl_2 administration. The Co^<2+>-treated rats drank water containing 0.01% CoCl_2. In the first experiment, training and Co^<2+> administration lasted for 5 weeks. Chronic Co^<2+> administration significantly increased the blood hemoglobin concentration by approximately 25% with and without training. Only in the diaphragm, the Co^<2+> treatment alone significantly increased total capillary density and the capillary-to-fiber ratio (C:F). Both training groups with and without Co^<2+> administration significantly increased the C:F in soleus (SOL) and plantaris (PL) muscles. In PL, the increase was significantly greater in the Co^<2+>-treated training group than in the non-Co^<2+>-treated training group. The densities of VEGF-positive capillaries (VEGF-cap) remained unchanged in all muscle portions examin … More ed after either Co^<2+> administration or exercise training. The second experiment was designed to examine the time course changes in VEGF expression and capillary geometry in the early stage of the treatment. After 6 and 10 days of the Co^<2+> administration, the VEGF-cap was significantly increased by 27% and 65%, respectively in SOL. After 10 days of Co^<2+> administration, the C:F was significantly increased. The training with Co^<2+> significantly increased the VEGF-cap by 69%, 44% and 60%, respectively, after 3, 6 and 10 days in SOL, while it significantly increased the VEGF-cap after 10 days in the mixed fiber portion of plantaris muscle (PLm). Training with or without Co^<2+> significantly increased the C:F after 6 and 10 days in the SOL. Training with Co^<2+>, but training alone did not, significantly increased the C:F in PLm after 10 days. In condition, the present results suggest that activation of the cellular oxygen-sensing mechanism induced by Co^<2+> administration facilitates microvascular remodeling in hind-leg muscles by facilitating an expression of VEGF. Less