The arterial baroreflex resets with orthostasis.
The arterial baroreflex resets with orthostasis.
复制标题
DOI：
10.3389/fphys.2012.00461
复制
发表时间：
2012
影响因子：
4
通讯作者：
Stewart JM
中科院分区：
文献类型：
--
作者：
Schwartz CE;Stewart JM
动脉压力反射位于颈动脉窦和主动脉弓沿线，对于血压的快速短期自主调节至关重要。过去，人们认为它们在运动过程中会失活，因为血压、心率和交感神经活动与血压的静息功能关系发生了根本性的变化。然而，人们发现颈动脉窦压力与 HR 或交感血管收缩之间的所有关系都保持其曲线 S 形形状，但会被重置或转移，以便在运动期间最好地保护血压。为了确定在直立过程中是否也会发生重置，我们检查了仰卧和直立倾斜时测量的动脉压力反射。我们研究了收缩压和心率（心迷走性压力反射）、平均血压和通气量（通气压力反射）以及舒张压和交感神经活动（交感压力反射）之间的关系。我们通过使用改良的牛津方法完成了这些测量，其中通过推注硝普钠，然后 1 分钟后推注去氧肾上腺素，使血压快速变化。心迷走神经和通气压力反射均被“重置”，增益或反应范围没有变化。相比之下，交感压力感受性反射增强并发生变化，导致外周阻力增加，从而提高了受试者对低血压的防御能力。这与运动过程中的发现形成鲜明对比，运动过程中活跃骨骼肌的外周阻力没有增加。这种差异可能对锻炼肌肉具有选择性，并且可能代表功能性交感神经的作用，运动代谢物通过这种作用干扰肾上腺素能血管收缩。
The arterial baroreflexes, located in the carotid sinus and along the arch of the aorta, are essential for the rapid short term autonomic regulation of blood pressure. In the past, they were believed to be inactivated during exercise because blood pressure, heart rate, and sympathetic activity were radically changed from their resting functional relationships with blood pressure. However, it was discovered that all relationships between carotid sinus pressure and either HR or sympathetic vasoconstriction maintained their curvilinear sigmoidal shape but were reset or shifted so as to best defend BP during exercise. To determine whether resetting also occurs during orthostasis, we examined the arterial baroreflexes measured supine and upright tilt. We studied the relationships between systolic BP and HR (the cardiovagal baroreflex), mean BP, and ventilation (the ventilatory baroreflex) and diastolic BP and sympathetic nerve activity (the sympathetic baroreflex). We accomplished these measurements by using the modified Oxford method in which BP was rapidly varied with bolus injections of sodium nitroprusside followed 1 min later by bolus injections of phenylephrine. Both the cardiovagal and ventilatory baroreflexes were “reset” with no change in gain or response range. In contrast, the sympathetic baroreflex was augmented as well as shifted causing an increase in peripheral resistance that improved the subjects’ defense against hypotension. This contrasts with findings during exercise in which peripheral resistance in active skeletal muscle is not increased. This difference is likely selective for exercising muscle and may represent the actions of functional sympatholysis by which exercise metabolites interfere with adrenergic vasoconstriction.
登录
查看更多内容
DOI：
10.1111/j.1748-1716.1972.tb05157.x
发表时间：
1972-01-01
期刊：
ACTA PHYSIOLOGICA SCANDINAVICA
影响因子：
--
作者：
DELIUS, W;HAGBARTH, KE;HONGELL, A
通讯作者：
HONGELL, A
影响因子：
37.8
作者：
Fu, Q;Witkowski, S;Levine, BD
通讯作者：
Levine, BD
影响因子：
1.4
作者：
HOARE, CAR
通讯作者：
HOARE, CAR
影响因子：
1.9
作者：
KENT, BB;DRANE, JW;MANNING, JW
通讯作者：
MANNING, JW
影响因子：
6.1
作者：
Kawasaki, Tatsuya;Kaimoto, Satoshi;Sugihara, Hiroki
通讯作者：
Sugihara, Hiroki