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Introduction: The autonomic effects of antidepressants and quetiapine on heart rate variability (HRV) are inconsistent based on past studies. The aim of this study was to explore their influence on the HRV of psychiatric patients without psychotic symptoms. Methods: A total of 94 patients with depression, anxiety, or somatic symptoms, were recruited into this study. Based on their medication, 4 groups were identified: the no antidepressant group (n = 19), the SSRI group (using sertraline or escitalopram, n = 53), the other antidepressants group (using venlafaxine or mirtazapine, n = 9), and the augmentation group (AG, using an antidepressant + quetiapine, n = 13). The HRV of the 4 groups were compared. The correlations between HRV and the medication(s) used were clarified. Results: Among the 4 groups, the AG had the lowest HRV with its total power (TP), very low frequency power (VLF) and low frequency power (LF) of HRV being significantly different from those of the other groups. Age and using quetiapine were found to be negatively correlated with TP, VLF and LF. With this study group, the autonomic effects of antidepressants were found not to be significant. Discussion: Among psychiatric patients without psychotic symptoms, quetiapine causes an overt decrease in HRV. [ABSTRACT FROM AUTHOR]

This study aimed to test the hypothesis that, during extended wakefulness, parasympathetic activity is associated with the depth of the subsequent recovery sleep in mice. Fourteen male C57BL/6 mice were implanted with electrodes for sleep recording. Continuous spectral analysis was performed on the electroencephalogram (EEG) to obtain theta power (6-9Hz) and delta power (0-4Hz), as well as the R-R interval signals in order to quantify the high-frequency power (HF) and normalized low-frequency power (LF%) that are used to assess parasympathetic and sympathetic activity, respectively. All animals underwent a sleep deprivation experiment and a control experiment (6-h intervention and 1-h recovery period) on two separate days. During sleep deprivation, HF and theta power during wakefulness were significantly higher than during the control wakefulness after the second hour and first hour, respectively. During recovery non-rapid eye movement sleep, there was a rebound in sleep time and delta power as well as an elevation in HF relative to control post-intervention sleep. Both the rise in HF and theta power during extended wakefulness were found to be positively correlated with the delta power rebound. Furthermore, the HF change during extended wakefulness was also correlated with the amount of sleep loss and the enhancement of waking theta power. Our finding suggests that waking parasympathetic activity intimately reflects the cumulative sleep pressure, suggesting a potential role to be an autonomic marker for sleep propensity., (Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.)

Hippocampal theta rhythm (4-12 Hz) can be observed during locomotor behavior, but findings on the relationship between locomotion speed and theta frequency are inconsistent if not contradictory. The inconsistency may be because of the difficulties that previous analyses and protocols have had excluding the effects of behavior training. We recorded the first or second voluntary wheel running each day, and assumed that theta frequency and activity are correlated with speed in different running phases. By simultaneously recording electroencephalography, physical activity, and wheel running speed, this experiment explored the theta oscillations during spontaneous running of the 12-h dark period. The recording was completely wireless and allowed the animal to run freely while being recorded in the wheel. Theta frequency and theta power of middle frequency were elevated before running and theta frequency, theta power of middle frequency, physical activity, and running speed maintained persistently high levels during running. The slopes of the theta frequency and theta activity (4-9.5 Hz) during the initial running were different compared to the same values during subsequent running. During the initial running, the running speed was positively correlated with theta frequency and with theta power of middle frequency. Over the 12-h dark period, the running speed did not positively correlate with theta frequency but was significantly correlated with theta power of middle frequency. Thus, theta frequency was associated with running speed only at the initiation of running. Furthermore, theta power of middle frequency was associated with speed and with physical activity during running when chronological order was not taken into consideration., (Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.)

Hippocampal theta wave can be induced by running and is linked to cognitive functions. The initiation and maintenance of hippocampal theta during a complete course of running, however, is not well understood. Using a treadmill exercise model, this study wirelessly recorded the hippocampal electroencephalogram, nuchal electromyogram, electrocardiogram, and three-dimensional accelerations of 15 male young rats. Although the speed of the treadmill was constant during the entire 30-min running course, the frequency (Frq) and amplitude (Amp) of hippocampal theta changed dynamically. During the first 24 s (phase I), the Frq, Amp, electromyogram amplitude (EMG), heart rate (HR), and physical activity (PA) all increased. The changes in the Frq, EMG, and PA were among the fastest and the change in the HR was the slowest. After 24 s (phase II), the Frq declined to near baseline but the Amp remained persistently high. The slope of the Frq, Amp, and HR over time during phase I was different to that during phase II. During phase II, the Frq and Amp were significantly correlated with the PA and EMG. We conclude that treadmill running can be classified into two phases based on hippocampal functioning, and hippocampal theta varies with exercise effort during the treadmill running., (Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.)

Previous studies have shown awareness of uremic dysfunction in end-stage renal disease (ESRD) patients. Dysautonomia in ESRD patients may be reversible after renal transplantation. We used a power spectral analysis (PSA) of heart rate variability (HRV) to assess alterations of autonomic activity in 14 controls and 14 nondiabetic hemodialysis ESRD patients who had undergone renal transplantation. Compared with matched control subjects, the power frequency determinations of low frequency (LF; 3.42 ln(ms(2)) vs 6.38 ln(ms(2)); P < .05 high frequency (HF; 2.29 ln(ms(2)) vs 5.27 ln(ms(2)); P < .05)), and total power (TP; 5.39 ln(ms(2)) vs 7.53 ln(ms(2)); P < .05) were significantly suppressed in ESRD patients undergoing hemodialysis. ESRD patients showed significantly improved HRV after renal transplantation. After renal transplantation, there was no significant difference in the TP (6.82 ln(ms(2)) vs 7.53 ln(ms(2)); P = .15) component between measurements in both patient subgroups. We further divided the ESRD patients into 2 groups based on their pretransplantation HRV, observing alterations in HRV after renal transplantation. Patients with significantly improved HRV were those with more suppressed HRV before transplantation (HF <3 In(ms(2)). Autonomic dysfunction in ESRD patients was not irreversible even if severe, and recovery was observed as early as 6 months after transplantation.