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目的:了解有氧运动对肺动脉高压大鼠肺动脉血管舒张反应的影响。方法:8周大的雄性SD大鼠,随机分为4组,分别是常氧不运动组(N)、常氧运动组(EX)、肺动脉高压不运动组(H)、肺动脉高压运动组(HE)。将大鼠每天暴露在氧浓度为15.6%～16.1%的环境中8小时,每周7次,制作肺动脉高压模型。运动组分别进行8周每天1小时5天/周游泳训练,第9周分离出大鼠肺动脉,检测4组动脉环乙酰胆碱(Ach)诱导的内皮依赖性和硝普钠(SNP)诱导的非内皮依赖性舒张反应。结果:肺动脉高压组大鼠的肺动脉环的内皮依赖性血管舒张功能明显下降,动脉环经NO途径的最大舒张反应明显降低,有氧运动对肺动脉高压大鼠肺动脉的舒张功能有一定的改善作用,与肺动脉高压对照组及常氧运动组比较差异有统计学意义。结论:实验结果证实有氧运动对NO介导的血管舒张功能的有益调节作用,部分被低氧效应所抵消。长期低氧效应超过有氧运动对肺动脉血管的作用这个现象,很可能与NO途径受损有关。 相似文献
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Kawano H Iemitsu M Gando Y Ishijima T Asaka M Aoyama T Ando T Tokizawa K Miyachi M Sakamoto S Higuchi M 《Journal of sports sciences》2012,30(3):241-246
The present study elucidated the effects of habitual rowing exercise on arterial stiffness and plasma levels of the vasoconstrictor endothelin-1 and the vasodilator nitric oxide (NO) in older men. Eleven rowers (68.0 ± 1.6 years) and 11 sedentary control older men (64.9 ± 1.1 years) were studied. Peak oxygen uptake (36.0 ± 1.7 vs. 27.7 ±1.9 ml · kg(-1) · min(-1)), leg press power (1346 ± 99 vs. 1077 ± 68 W), and HDL-cholesterol (75 ± 5 vs. 58 ±3 mg · ml(-1)) were higher and triglyceride (78 ± 9 vs. 120 ± 14 mg · ml(-1)) was lower in rowers than in control participants (all P < 0.05). Arterial stiffness indices (carotid β-stiffness and cardio-ankle vascular index) and plasma endothelin-1 and NOx (nitrite + nitrate) levels did not differ between the two groups. These results suggest that habitual rowing exercise in older men is associated with high muscle power and aerobic capacity, and favourable blood lipid profile without affecting arterial stiffness or plasma levels of endotheline-1 and NO. 相似文献
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目的:探究低负荷加压训练对自发性高血压大鼠的降压效果及其作用机制。方法:选取4周龄雄性自发性高血压大鼠,随机分为对照组(高血压安静组)、低负荷训练组、低负荷加压训练组和高负荷训练组。低负荷训练组进行35%~55%1RM递进式低负荷爬梯训练,低负荷加压训练组进行30%~40%血流受限结合35%~55%1RM递进式低负荷爬梯训练,高负荷训练组进行55%~75%1RM递进式高负荷爬梯训练,训练后测定血压、血液中内皮素-1、血管内皮生长因子、一氧化氮合成酶的表达和心肌组织中内皮型一氧化氮合成酶的表达。结果:1)与对照组、高负荷训练组相比,低负荷加压训练组收缩压、舒张压显著下降(P<0.05);与低负荷训练组相比,低负荷加压训练组舒张压显著下降(P<0.05)。2)与对照组相比,低负荷加压训练组血液中内皮素-1表达显著下调(P<0.05),血管内皮生长因子和一氧化氮合成酶表达显著上调(P<0.05);3)与对照组相比,低负荷加压训练组心肌中内皮型一氧化氮合成酶表达显著上调(P<0.05);4)在低负荷加压训练组中,收缩压与内皮素-1呈正相关,相关性分析具有统计学意义(P<0.05);收缩压与一氧化氮合成酶、血管内皮生长因子、内皮型一氧化氮合成酶均呈负相关,相关性分析具有统计学意义(P<0.05)。结论:1)低负荷加压训练降压效果优于高负荷训练;2)低负荷加压训练能够通过下调血液中内皮素-1的表达,上调血液中血管内皮生长因子和一氧化氮合成酶的表达,同时上调心肌中内皮型一氧化氮合成酶表达,改善内皮细胞功能,达到降压的效果。 相似文献
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不同强度运动对大鼠冠状动脉CGRP、ET- 1 和NOS 表达的影响 总被引：1，自引：0，他引：1
目的:探讨运动对大鼠冠状动脉降钙素基因相关肽(CGRP)、内皮素(ET-1)和一氧化氮合酶(NOS)表达的影响.方法:健康雄性SD3月龄大鼠24只,分为安静对照组、小强度运动组和大强度运动组,运动组采用大鼠跑台运动方式,建立大鼠不同强度运动模型,运用免疫组织化学SABC法研究不同强度运动对大鼠冠状动脉CGRP、ET-1、神经型一氧化氮合酶(nNOS)、诱导型一氧化氮合酶(iNOS)和内皮型一氧化氮合酶(eNOS)表达的影响.结果:与安静对照组比较,小强度运动组和大强度运动组CGRP、nNOS、iNOS和eNOS均显著性升高,小强度运动组ET-1显著降低,大强度运动组ET-1显著性升高.与小强度运动组比较,大强度运动组CGRP、ET-1、nNOS、iNOS和eNOS的表达变化均有显著性差异.小强度运动组和大强度运动组ET-1/CGRP和ET-1/NOS比值均低于安静对照组.结论:运动可引起大鼠冠状动脉CGRP、ET-1及NOS的表达变化,且与运动强度关系密切.因此认为,不同强度运动引起ET-1/CGRP和ET-1/NOS比值的变化可能是运动引起心血管生物功能改变的因素之一. 相似文献
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不同训练强度对间歇性缺氧大鼠骨骼肌NO和NOS的影响 总被引：6，自引：0，他引：6
利用低氧舱技术模拟“高住低练”环境,观察间歇性缺氧条件和两种不同运动训练强度对骨骼肌NO和NOS的共同作用效应。SD雄性大鼠50只,随机分为6组:(1)常氧对照组(NC),(2)常氧低强度运动组(NEL),(3)常氧高强度运动组(NEH),(4)低氧对照组(HC),(5)低氧低强度运动组(HEL),(6)低氧高强度运动组(HEH)。低氧组每日20时至次日8时置于低氧舱中,其余时间置于常氧环境下。低氧舱氧浓度控制在14.7%,相当于海拔高度大约2800米。运动组每天在常氧环境中进行30分钟跑台训练,速度定为26.8米/分钟,低强度运动组坡度0度,高强度运动组坡度15度。9周后各组大鼠于安静状态进行宰杀,取股四头肌,匀浆进行NO含量和NOS活性检测。结果显示:常氧高强度运动组股四头肌NO水平与常氧对照组相比呈升高趋势并接近显著性水平(p=0.052)。低氧低运动强度组NO显著高于其他组,NOS变化组间比较均未达显著性水平。说明常氧条件下,高强度运动强度才能使NO释放增加。而在间歇性缺氧条件下,较低强度运动即可使NO释放明显增加。提示间歇性缺氧条件可使引起NO释放的运动强度阈值下降。 相似文献
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一氧化氮及其合酶与运动的关系 总被引：8，自引：0，他引：8
一氧化氮（ＮＯ）是一种强扩血管物质,近年来倍受人们重视。笔者介绍了一氧化氮、一氧化氮合酶（ＮＯＳ）在人体中的产生、调节及其他生物学作用,并重点综述了体育运动对ＮＯ、ＮＯＳ的影响。这些结果对深刻认识低氧训练以及训练对心血管系统的作用等有着重要参考价值。 相似文献
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目的:探讨体育锻炼对老年Ⅱ型糖尿病患者身体形态、身体素质、身体机能及动脉阶段弹性的影响。方法:根据体育锻炼问卷结果将受试者分为锻炼组(n=73)和非锻炼组(n=49)进行相关指标的观察。结果:锻炼组的形态、机能、素质类指标多数优于非锻炼组,锻炼组与不锻炼组相比,除体重和血压不具有统计学差异外,其余指标均具有显著性差异;锻炼组肱动脉—踝动脉脉搏波传导速度显著低于非锻炼组,但踝臂指数与非锻炼组无显著性差异。结论:经常参加体育锻炼可增强老年Ⅱ型糖尿病患者的体质,提高老年Ⅱ型糖尿病患者的动脉顺应性。 相似文献
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The aim of this study was to determine the effects of a single bout of endurance exercise on subsequent strength performance. Eight males with a long history of resistance training performed isokinetic, isometric and isotonic leg extension strength tests 8 and 32 h after 50 min of cycle ergometry at 70-110% of critical power. The participants also completed a control condition in which no cycling was performed. Plasma lactate and ammonia were measured before and immediately after each strength test. Isokinetic, isometric and isotonic leg extension torques were not significantly different 8 or 32 h after endurance exercise compared with the control condition (P > 0.05). A large (50.3%), but not statistically significant, increase in plasma ammonia was evident during the strength tests performed 8 h after endurance exercise, while a significant (P < 0.05) increase in ammonia was also seen 32 h after endurance exercise. No significant changes in plasma ammonia were evident in the control condition. Our results suggest that leg extension strength was not compromised by an earlier bout of endurance cycling. However, metabolic activity during the strength tests might have been altered by the preceding bout of endurance exercise. 相似文献
9.
Michael Leveritt Helen MacLaughlin Peter J. Abernethy 《Journal of sports sciences》2013,31(11):865-871
The aim of this study was to determine the effects of a single bout of endurance exercise on subsequent strength performance. Eight males with a long history of resistance training performed isokinetic, isometric and isotonic leg extension strength tests 8 and 32 h after 50 min of cycle ergometry at 70-110% of critical power. The participants also completed a control condition in which no cycling was performed. Plasma lactate and ammonia were measured before and immediately after each strength test. Isokinetic, isometric and isotonic leg extension torques were not significantly different 8 or 32 h after endurance exercise compared with the control condition ( P > 0.05). A large (50.3%), but not statistically significant, increase in plasma ammonia was evident during the strength tests performed 8 h after endurance exercise, while a significant ( P ? 0.05) increase in ammonia was also seen 32 h after endurance exercise. No significant changes in plasma ammonia were evident in the control condition. Our results suggest that leg extension strength was not compromised by an earlier bout of endurance cycling. However, metabolic activity during the strength tests might have been altered by the preceding bout of endurance exercise. 相似文献
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本研究对长期坚持参加太极拳运动中老年女性血清一氧化氮(NO)及其合酶(NOS)活性进行测定,同时测定胆固醇(TC)、高密度脂蛋白(HDL-c)、甘油三脂(TG)、血糖(GLU)等指标。结果表明:(1)长期有规律的太极拳运动可以提高中老年女性机体NOS活性,可以促进NO的生成。(2)长期进行有规律的太极拳运动可以提高机体高密度脂蛋白水平、降低胆固醇水平,预防动脉粥样化。 相似文献
13.
为了探讨杏仁体一氧化氮合酶 (NOS)与运动性疲劳的关系 ,研究了运动性疲劳对大鼠杏仁体 NOS表达的影响。经 4周大强度游泳训练制成大鼠运动疲劳模型 ,在安静状态下 ,用放射免疫学方法检侧了大鼠杏仁体 NOS活性。结果表明 ,疲劳组大鼠杏仁体 NOS总活性小于对照组 (P<0 .0 5 )。认为运动性疲劳作为一种应激可使大鼠杏仁体神经元中的 NOS下调 ,杏仁体NOS神经元参与了中枢运动性疲劳的形成 ,其机理可能与杏仁体神经元对应激反应的心理、行为、内分泌调节以及 NO的神经毒性有关。 相似文献
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Kevin T. Mattocks J. Grant Mouser Matthew B. Jessee Samuel L. Buckner Scott J. Dankel Zachary W. Bell 《Journal of sports sciences》2019,37(16):1857-1864
The purpose was to examine changes in the perceptual responses to lifting a very low load (15% one repetition maximum (1RM)) with and without (15/0) different pressures [40% (15/40) and 80% (15/80) arterial occlusion pressure] and compare that to traditional high load (70/0) resistance exercise. Ratings of perceived exertion (RPE) and discomfort were measured following each set of exercise. In addition, resting arterial occlusion pressure was measured prior to exercise. Assessments were made in training sessions 1, 9, and 16 for the upper and lower body. Data are presented as means and 95% CI. There were changes in RPE in the upper body with condition 15/40 [?2.1 (?3.4, ?0.850)] and 15/80 [?2.4 (?3.6, ?1.1)] decreasing by the end of training. In the lower body, RPE decreased in condition 15/40 [?1.4 (?2.3, ?0.431)] by the end of the training study. There was a main effect of time in the upper body with all conditions decreasing discomfort. In the lower body, all conditions decreased except for 15/80. For arterial occlusion pressure, there were differences across time in the 15/40 condition and the 15/80 condition in the upper body. Repeated exposure to blood flow restriction may dampen the perceptual responses over time. 相似文献
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There is a paucity of research on devices suitable for home-based isometric exercise. Our aim was to compare cardiovascular responses to isometric exercise using novel and established methods. Ten individuals (age 34.0 +/- 8.5 years, mass 68.2 +/- 10.4 kg, height 1.72 +/- 0.09 m; mean +/- s) performed three different isometric exercise protocols with 48 h between each. Each protocol involved four repeated exercise bouts of 2 min at 30% maximum voluntary contraction force using alternate legs (transducer), alternate arms (transducer), or alternate arms (novel device). Systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate were measured every 30 s. The highest (peak) values during each 2 min bout of exercise were recorded (peak systolic blood pressure, peak diastolic blood pressure, peak mean arterial blood pressure and peak heart rate). At the end of each 2 min exercise bout, the participants rated their perceived discomfort using Borg's CR-10 scale. There was a statistically significant difference in peak systolic blood pressure between isometric arm flexion using the force transducer and the novel device [158.1 +/- 10.8 vs. 149.1 +/- 13.9 mmHg (mean +/- s); P = 0.02]. Further analysis showed that peak systolic blood pressure was on average 9 mmHg higher using the force transducer with limits of agreement of - 15.97 to 33.97 mmHg. Analysis of the peak diastolic blood pressure, peak mean arterial blood pressure, peak heart rate and CR-10 data revealed no statistically significant differences between the three protocols. These results suggest that this novel, home-based method elicited similar cardiovascular responses during isometric exercise to those of established laboratory-based methods. However, the lower peak systolic blood pressure using the modified scales warrants further investigation before this method is used widely in the home. 相似文献
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Chris Mawhinney Helen Jones David A. Low Daniel J. Green Glyn Howatson Warren Gregson 《European Journal of Sport Science》2017,17(5):519-529
This study determined the influence of cold (8°C) and cool (22°C) water immersion on lower limb and cutaneous blood flow following resistance exercise. Twelve males completed 4 sets of 10-repetition maximum squat exercise and were then immersed, semi-reclined, into 8°C or 22°C water for 10-min, or rested in a seated position (control) in a randomized order on different days. Rectal and thigh skin temperature, muscle temperature, thigh and calf skin blood flow and superficial femoral artery blood flow were measured before and after immersion. Indices of vascular conductance were calculated (flux and blood flow/mean arterial pressure). The colder water reduced thigh skin temperature and deep muscle temperature to the greatest extent (P?<?.001). Reductions in rectal temperature were similar (0.2–0.4°C) in all three trials (P?=?.69). Femoral artery conductance was similar after immersion in both cooling conditions, with both conditions significantly lower (55%) than the control post-immersion (P?<?.01). Similarly, there was greater thigh and calf cutaneous vasoconstriction (40–50%) after immersion in both cooling conditions, relative to the control (P?<?.01), with no difference between cooling conditions. These findings suggest that cold and cool water similarly reduce femoral artery and cutaneous blood flow responses but not muscle temperature following resistance exercise. 相似文献
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The aim of this study was to compare the 'anaerobic threshold' (AnT) of subjects determined during a continuous 2-min incremental exercise test until exhaustion and the 'maximal lactate steady-state' (BLaSsmax) determined during prolonged exercise at constant loads corresponding to the subjects' AnT and/or 5-25% above and below it. Seventeen subjects performed an incremental exercise test and 1-5 prolonged exercise tests on a cycle ergometer until exhaustion at intervals of 1 week, and work rates, oxygen uptake (VO2) values and brachial venous blood lactate (BLa) levels were measured. It was proposed that when exercising at a constant workload below AnT, BLa would fall after having reached its peak; at the level of AnT, BLa reaches maximal steady-state (BLaSsmax); and above AnT, BLa increases continuously. Altogether, in 34 of 45 tests with a constant workload between 80 and 125% AnT, BLa values were as expected. In those cases in which BLaSsmax was reached, BLa increased on average by 3.8 mM from resting levels. This increase was 2.0 mM greater than that seen between resting levels and AnT during incremental exercise. There was no correlation between BLa values at BLaSsmax and at AnT, both when expressed as an increase in BLa (delta BLa) and absolute BLa concentration. Altogether, 81% of the variation in BLa concentration at BLaSsmax could be explained by the subjects' age, the percentage of slow-twitch fibres and BLa levels at rest. The AnT and BLaSsmax did not differ significantly, and these values were correlated (r = 0.83). Together, AnT and age accounted for 85% of the variation seen in BLaSsmax. The BLaSsmax did not correlate with AnT when fixed at a BLa concentration of 4 mM (AnT4mM). The three hypotheses tested in this study were confirmed, and the present results demonstrate that AnT correlates with BLaSsmax. The few exceptions to anticipated BLa kinetics were small in magnitude and could be explained by physiological variations. 相似文献
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Jonathan D Wiles Damian Coleman Martin Dunford Ian Swaine 《Journal of sports sciences》2013,31(8):795-803
There is a paucity of research on devices suitable for home-based isometric exercise. Our aim was to compare cardiovascular responses to isometric exercise using novel and established methods. Ten individuals (age 34.0?±?8.5 years, mass 68.2?±?10.4?kg, height 1.72?±?0.09?m; mean?±?s) performed three different isometric exercise protocols with 48?h between each. Each protocol involved four repeated exercise bouts of 2?min at 30% maximum voluntary contraction force using alternate legs (transducer), alternate arms (transducer), or alternate arms (novel device). Systolic blood pressure, diastolic blood pressure, mean arterial blood pressure and heart rate were measured every 30?s. The highest (peak) values during each 2?min bout of exercise were recorded (peak systolic blood pressure, peak diastolic blood pressure, peak mean arterial blood pressure and peak heart rate). At the end of each 2?min exercise bout, the participants rated their perceived discomfort using Borg's CR-10 scale. There was a statistically significant difference in peak systolic blood pressure between isometric arm flexion using the force transducer and the novel device [158.1?±?10.8 vs. 149.1?±?13.9?mmHg (mean?±?s); P = 0.02]. Further analysis showed that peak systolic blood pressure was on average 9?mmHg higher using the force transducer with limits of agreement of –?15.97 to 33.97?mmHg. Analysis of the peak diastolic blood pressure, peak mean arterial blood pressure, peak heart rate and CR-10 data revealed no statistically significant differences between the three protocols. These results suggest that this novel, home-based method elicited similar cardiovascular responses during isometric exercise to those of established laboratory-based methods. However, the lower peak systolic blood pressure using the modified scales warrants further investigation before this method is used widely in the home. 相似文献
20.
The relationships between exercise intensity, heart rate, and blood pressure during an incremental isometric exercise test 总被引：1，自引：0，他引：1
Currently, it is not possible to prescribe isometric exercise at an intensity that corresponds to given heart rates or systolic blood pressures. This might be useful in optimizing the effects of isometric exercise training. Therefore, the aim of this study was to explore the relationships between isometric exercise intensity and both heart rate and systolic blood pressure during repeated incremental isometric exercise tests. Fifteen participants performed seated isometric double-leg knee extension, during which maximum voluntary contraction (MVC) was assessed, using an isokinetic dynamometer. From this, a corresponding peak electromyographic activity (EMG(peak)) was determined. Subsequently, participants performed two incremental isometric exercise tests (at least 48 h apart) at 10, 15, 20, 25, and 30% EMG(peak), during which steady-state heart rate and systolic blood pressure were recorded. In all participants, there were linear relationships between %EMG(peak) and heart rate (r at least 0.91; P < 0.05) and between %EMG(peak) and systolic blood pressure (r at least 0.92; P < 0.05). Also, when repeated tests were compared, there were no differences in the slopes (P > 0.50) or elevations (P > 0.10) for either of the relationships. Therefore, these linear relationships could be used to identify isometric exercise training intensities that correspond to precise heart rates or systolic blood pressures. Training performed in this way might provide greater insight into the underlying mechanisms for the cardiovascular adaptations that are known to occur as a result. 相似文献