Hayano J, Mukai S, Sakakibara M, Okada A, Takata K, Fujinami T
Third Department of Internal Medicine, Nagoya City University Medical School, Japan.
Am J Physiol. 1994 Jul;267(1 Pt 2):H33-40. doi: 10.1152/ajpheart.1994.267.1.H33.
To determine whether paced breathing (PB) and respiratory interval of PB modify the relationship between spectral components of heart rate variability (HRV) and cardiac vagal tone, we studied seven healthy young males under the condition of beta-adrenergic blockade by intravenous propranolol (0.2 mg/kg). Compared with spontaneous breathing, PB at the same respiratory interval as that of individual spontaneous breathing showed no significant effect on the amplitude of the high-frequency (HF) component or the mean R-R interval in either the supine or tilt position, whereas the PB decreased the amplitude of the low-frequency (LF; 0.04-0.15 Hz) component in both positions (P = 0.004 and 0.042, respectively). When the respiratory interval was increased from 3 to 6 s, the HF amplitude showed a progressive increase in both positions (P = 0.001 and 0.035, respectively), while the LF amplitude and mean R-R interval remained unchanged. These results indicate that the effects of PB and respiratory interval on the spectral components of HRV are not mediated by the changes in mean cardiac vagal tone and support the hypothesis that increased respiratory interval amplifies the respiratory-related vagal modulation of heart rate.
为了确定定频呼吸（PB）及其呼吸间隔是否会改变心率变异性（HRV）频谱成分与心脏迷走神经张力之间的关系，我们对7名健康年轻男性进行了研究，研究在静脉注射普萘洛尔（0.2 mg/kg）导致β-肾上腺素能阻滞的条件下进行。与自主呼吸相比，与个体自主呼吸呼吸间隔相同的PB，在仰卧位或倾斜位时，对高频（HF）成分的幅度或平均R-R间期均无显著影响，而PB在两个体位均降低了低频（LF；0.04 - 0.15 Hz）成分的幅度（分别为P = 0.004和0.042）。当呼吸间隔从3秒增加到6秒时，两个体位的HF幅度均呈逐渐增加趋势（分别为P = 0.001和0.035），而LF幅度和平均R-R间期保持不变。这些结果表明，PB和呼吸间隔对HRV频谱成分的影响不是由平均心脏迷走神经张力的变化介导的，并支持呼吸间隔增加会放大心率的呼吸相关迷走神经调节这一假说。
