Short term fluctuations in muscle sympathetic nerve activity in man.
In order to characterize the variability of muscle sympathetic nerve activity (MSNA), resting MSNA was recorded for over 30 min in 4 healthy young subjects in the supine position in a thermoneutral environment. Spectral analysis was applied to the integrated traces of MSNA and to the heart rate using maximum entropy method. Both MSNA and the heart rate spectra exhibited periodic peaks, which were superimposed on the general 1/f-like structure, at around 0.02 Hz, 0.1 Hz, 0.25 Hz and 1.0 Hz. However, the periodic peak at 0.1 Hz in the MSNA spectra was more prominent than in the heart rate spectra at the same frequency. These findings suggest that MSNA variability may have a closer causal relationship with Mayer's rhythm than with heart rate fluctuations.
Sugiyama
Y
Y
Department of Autonomic and Behavioral Neurosciences, Division of Higher Nervous Control, Research Institute of Environmental Medicine, Nagoya University, Nagoya, Japan.
Mano
T
T
D000328:Adult; D004562:Electrocardiography; D006339:Heart Rate / Q000502:physiology*; D006801:Humans; D008297:Male; D018482:Muscle, Skeletal / Q000294:innervation* / Q000502:physiology; D016683:Supine Position / Q000502:physiology; D013564:Sympathetic Nervous System / Q000502:physiology*; D013979:Tibial Nerve / Q000502:physiology*