Oscillatory patterns in sympathetic neural discharge and cardiovascular variables during orthostatic stimulus
Oscillatory patterns in sympathetic neural discharge and cardiovascular variables during orthostatic stimulus
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DOI：
10.1161/01.cir.101.8.886
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发表时间：
2000-02-29
期刊：
影响因子：
37.8
通讯作者：
Mosqueda-Garcia, R
中科院分区：
文献类型：
--
作者：
Furlan, R;Porta, A;Mosqueda-Garcia, R
背景：我们测试了一个假设，即在平视倾斜动作引起的交感神经活动生理增加过程中，一种共同的振荡模式可能表征了肌肉交感神经活动（MSNA）的节律性放电以及心率和动脉收缩压（SAP）的自发变异性。方法与结果：10例健康受试者连续记录心电图、动脉压、呼吸活动、中心静脉压。和MSNA，在平卧位和75度俯仰时。静息和倾斜第5分钟时采集静脉儿茶酚胺评估样本，对R-R间隔、SAP和MSNA变异和呼吸活动进行频谱和交叉频谱分析，提供每个信号的低（LF, 0.1 Hz）和高频（HF, 0.27 Hz）节奏成分，并评估它们的线性关系。与平卧位相比。倾斜降低中心静脉压，但血压不变。心率、MSNA、血浆肾上腺素和去甲肾上腺素水平升高，表明整体交感神经活动显著增强。俯卧时LFMSNA较仰卧时升高；LFMSNA的增加与交感神经放电量成正比。与静止时相比，倾斜时MSNA的LF分量与R-R区间和SAP变异之间的耦合增强。结论：在倾斜诱导的交感神经激活过程中，基于LF节律性增加的类似振荡模式表征了神经交感放电、R-R间隔和动脉压的自发变异性。
Background-We tested the hypothesis that a common oscillatory pattern might characterize the rhythmic discharge of muscle sympathetic nerve activity (MSNA) and the spontaneous variability of heart rate and systolic arterial pressure (SAP) during a physiological increase of sympathetic activity induced by the head-up tilt maneuver.Methods and Results-Ten healthy subjects underwent continuous recordings of EGG, intra-arterial pressure, respiratory activity, central venous pressure. and MSNA, both in the recumbent position and during 75 degrees head-up tilt. Venous samplings for catecholamine assessment were obtained at rest and during the fifth minute of tilt, Spectrum and cross-spectrum analyses of R-R interval, SAP, and MSNA variabilities and of respiratory activity provided the low (LF, 0.1 Hz) and high frequency (HF, 0.27 Hz) rhythmic components of each signal and assessed their linear relationships. Compared with the recumbent position. tilt reduced central venous pressure, but blood pressure was unchanged. Heart rate, MSNA, and plasma epinephrine and norepinephrine levels increased, suggesting a marked enhancement of overall sympathetic activity. During tilt, LFMSNA increased compared with the level in the supine position; this mirrored similar changes observed in the LF components of R-R interval and SAP variabilities, The increase of LFMSNA was proportional to the amount of the sympathetic discharge. The coupling between LF components of MSNA and R-R interval and SAP variabilities was enhanced during tilt compared with rest.Conclusions-During the sympathetic activation induced by tilt, a similar oscillatory pattern based on an increased LF rhythmicity characterized the spontaneous variability of neural sympathetic discharge, R-R interval, and arterial pressure.