Fragrance inhalation of essential oils is widely used in aromatherapy, and it is known to affect blood pressure (BP) and heart rate (HR) via autonomic control of circulation. In this study, we aimed to test the hypothesis that the changes in hemodynamics with fragrance inhalation were observed along with changes in muscle sympathetic nerve activity (MSNA). In study 1, thirteen healthy men were exposed to fragrance stimulation of grapefruit essential oil for 10 min, and BP, HR, and MSNA were continuously measured. In study 2, another nine healthy men were exposed to the same fragrance stimulation; responses in BP and HR were continuously measured, and plasma noradrenaline and cortisol concentrations were determined. We found that diastolic BP increased significantly during fragrance inhalation, while the other variables remained unchanged in both studies. Although MSNA burst frequency, burst incidence, and total activity remained unchanged during fragrance inhalation, we found a significant linear correlation between changes in diastolic BP in the last 5 min of fragrance inhalation and changes in MSNA burst frequency. The plasma cortisol concentration decreased significantly at 10 min of fragrance inhalation, though the noradrenaline concentration remained unchanged. These results suggest, for the first time, that changes in BP with fragrance inhalation of essential oil are associated with changes in MSNA even with decreased stress hormone.

中文翻译：

---

吸入柚子香精油引起的舒张压升高与肌肉交感神经活动呈正相关。

香精油的香薰吸入已广泛用于芳香疗法中，并且已知通过自主控制循环会影响血压（BP）和心率（HR）。在这项研究中，我们旨在检验以下假设：观察到随着香气吸入而发生的血流动力学变化以及肌肉交感神经活动（MSNA）的变化。在研究1中，有13位健康的男性接受了葡萄柚精油的芳香刺激10分钟，并连续测量了BP，HR和MSNA。在研究2中，另外9名健康男性受到了相同的香气刺激。连续测量BP和HR的反应，并测定血浆去甲肾上腺素和皮质醇浓度。我们发现在吸入香气期间舒张压BP显着增加，而其他变量在两项研究中均保持不变。尽管在吸入香气期间MSNA的爆发频率，爆发发生率和总活性保持不变，但是我们发现在吸入香气的最后5分钟内舒张压BP的变化与MSNA爆发频率的变化之间存在显着的线性相关性。尽管去甲肾上腺素浓度保持不变，但在吸入香精10分钟后血浆皮质醇浓度显着下降。这些结果首次表明，香精吸入香精油后血压的变化与MSNA的变化有关，甚至与压力激素降低有关。我们发现在吸入香气的最后5分钟内舒张压BP的变化与MSNA猝发频率的变化之间存在显着的线性相关性。尽管去甲肾上腺素浓度保持不变，但在吸入香精10分钟后血浆皮质醇浓度显着下降。这些结果首次表明，通过吸入香精油而使血压变化与MSNA的变化有关，甚至与压力激素的降低有关。我们发现在吸入香气的最后5分钟内舒张压BP的变化与MSNA猝发频率的变化之间存在显着的线性相关性。尽管去甲肾上腺素浓度保持不变，但在吸入香精10分钟后血浆皮质醇浓度显着下降。这些结果首次表明，香精吸入香精油后血压的变化与MSNA的变化有关，甚至与压力激素降低有关。