Effects of exercise pressor reflex activation on carotid baroreflex function during exercise in humans
Effects of exercise pressor reflex activation on carotid baroreflex function during exercise in humans
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DOI：
10.1111/j.1469-7793.2001.t01-2-00871.x
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发表时间：
2001-06-15
影响因子：
5.5
通讯作者：
Secher, NH
中科院分区：
文献类型：
--
作者：
Gallagher, KM;F'adel, PJ;Secher, NH
1.本研究旨在探讨运动加压反射对颈动脉压力感受性反射重调定的作用. 10名受试者在两种条件下进行3.5分钟的静态单腿运动（20%最大自主收缩）和7分钟的动态自行车运动（20%最大摄氧量）：对照（无干预）和应用充气至100 mmHg的医用抗休克（MAS）裤（以激活运动按压反射）。颈动脉压力感受性反射功能测定采用快速颈压/颈吸技术.在运动过程中，与对照组相比，MAX裤子的应用（MAX条件）增加了平均动脉压（MAP）、血浆去甲肾上腺素浓度（仅动力运动）和主观用力（仅动力运动）（P < 0.05）。MAX条件对静息状态无明显影响。MAX条件对心率（HR）、血浆乳酸和肾上腺素浓度或休息和运动时的摄氧量没有影响。颈动脉压力感受器反射刺激-反应曲线在反应臂上向上重置，并通过控制运动在不改变增益的情况下恢复到更高的工作压力。MAX裤子对运动加压反射的激活进一步重置了MAP的颈动脉压力感受器反射控制，如曲线的向上和向下重新定位所示。然而，颈动脉压力感受器反射控制的HR只是转移到更高的工作压力的MAX裤子。颈动脉压力感受器反射的敏感性不受运动加压反射激活的影响.这些结果表明，在动态和静态运动中，运动加压反射能够主动重置颈动脉压力感受器反射对平均动脉压的控制，但它似乎只调制颈动脉压力感受器反射对心率的控制。
1. This investigation was designed to determine the contribution of the exercise presser reflex to the resetting of the carotid baroreflex during exercise.2. Ten subjects performed 3.5 min of static one-legged exercise (20% maximal voluntary contraction) and 7 min dynamic cycling (20 % maximal oxygen uptake) under two conditions: control (no intervention) and with the application of medical anti-shock (MAS) trousers inflated to 100 mmHg (to activate the exercise presser reflex). Carotid baroreflex function was determined at rest and during exercise using a rapid neck pressure/neck suction technique.3. During exercise, the application of MAX trousers (MAX condition) increased mean arterial pressure (MAP), plasma noradrenaline concentration (dynamic exercise only) and perceived exertion (dynamic exercise only) when compared to control (P < 0.05). No effect of the MAX condition was evident at rest. The MAX condition had no effect on heart rate (HR), plasma lactate and adrenaline concentrations or oxygen uptake at rest and during exercise. The carotid baroreflex stimulus-response curve was reset upward on the response arm and rightward to a higher operating pressure by control exercise without alterations in gain. Activation of the exercise presser reflex by MAX trousers further reset carotid baroreflex control of MAP, as indicated by the upward and rightward relocation of the curve. However, carotid baroreflex control of HR was only shifted rightward to higher operating pressures by MAX trousers. The sensitivity of the carotid baroreflex was unaltered by exercise presser reflex activation.4. These findings suggest that during dynamic and static exercise the exercise presser reflex is capable of actively resetting carotid baroreflex control of mean arterial pressure; however, it mould appear only to modulate carotid baroreflex control of heart rate.