The Correlation of Mean Sympathetic Activity with Low-Frequency Blood Pressure and Sympathetic Variability
Journal
Clinical and Experimental Hypertension
Journal Volume
31
Journal Issue
7
Pages
615--624
Date Issued
2009-01
Author(s)
Meng-Li Tsai
Wan-Ting Tseng
Chen-Tung Yen
Ruei-Feng Chen
Tsai, M.-L.
Tseng, W.-T.
Yen, C.-T.
Chen, R.-F.
Tsai, M.-L.
Tseng, W.-T.
Yen, C.-T.
Chen, Yao-liang
Chen, R.-F.
Abstract
The low-frequency (0.2-0.8 Hz) component of blood pressure (BP) variability (LF(BP)) is used as an index of the low-frequency variability of sympathetic nerve activity (SNA) (LF(SNA)) in rats. It is unclear whether the LF(BP) can be used as an index of the mean SNA (mSNA). We investigated the correlation of the LF(BP) with different levels of the mSNA in this study to evaluate if it is a feasible tool for detecting differences in mSNA under physiological conditions. Correlation of the LF(SNA) with different mSNA levels was also investigated. The BP and renal SNA of rats were recorded in a nonanesthetized state. Values of the mSNA obtained from 531 recording epochs in six rats were graded into 30 levels with a bin resolution of 0.05 normalized units. A linear regression analysis showed that the correlation between the mSNA and LF(SNA) was higher than that between the mSNA and LF(BP). The mSNA was well correlated with the LF(SNA) over a wider mSNA range, while it was correlated with the LF(BP) only in a restricted range. These results demonstrated a restricted condition under which measuring the LF(BP) can be a definitive index of the mSNA, and further suggest the possibility of using the weighted LF(BP) as an index of the mSNA via intermediation by the LF(SNA) for a wider mSNA range.
SDGs
Type
journal article