Resting parasympathetic nervous system activity is associated with greater antiviral gene expression

Parasympathetic nervous system activity can downregulate inflammation, but it remains unclear how parasympathetic nervous system activity relates to antiviral activity. The present study examined associations between parasympathetic nervous system activity and cellular antiviral gene regulation in 90 adolescents (M_age = 16.28, SD = 0.73; 51.1% female) who provided blood samples and measures of cardiac respiratory sinus arrhythmia (RSA), twice, five weeks apart. Using a multilevel analytic framework, we found that higher RSA (an indicator of higher parasympathetic nervous system activity)—both at rest and during paced breathing—was associated with higher expression of Type I interferon (IFN) response genes in circulating leukocytes, even after adjusting for demographic and biological covariates. RSA was not associated with a parallel measure of inflammatory gene expression. These results identify a previously unrecognized immunoregulatory aspect of autonomic nervous system function and highlight a potential biological pathway by which parasympathetic nervous system activity may relate to health.     

The effect of intranasal administration of oxytocin on fear recognition

The oxytocinergic system has recently been placed amongst the most promising targets for various psychiatric treatments due to its role in prosocial behavior and anxiety reduction. Although recent studies have demonstrated a general effect of administration of oxytocin on emotion recognition, no study to date has examine the effect of oxytocin on each emotion separately. In the present study, a double-blind placebo-controlled crossover design was used in a dynamic facial expression task, in order to assess the effects of administration of oxytocin on emotion recognition. A single dose of oxytocin or a placebo was administered intranasally to 27 healthy male subjects 45 min prior to task performance. The results showed that a single intranasal administration of oxytocin, as opposed to the placebo, improved the subjects’ ability to recognize fear, but not other emotions. These results suggest a specific role for oxytocin in fear recognition, which could be relevant for clinical disorders that manifest deficits in processing emotional facial expressions, particularly fear.     

Autonomic responses and neural-cardiac coupling during individually tailored symptom provocation in obsessive-compulsive disorder

Elevated anxiety in obsessive-compulsive disorder (OCD) has been linked to cortico-limbic hyperactivation, whereas hyperarousal of the autonomous nerve system (ANS) has inconsistently been found. We investigate ANS functioning during symptom provocation with individually tailored OCD-relevant pictures in 14 unmedicated patients and 14 controls and link it to activation in brain areas involved in ANS regulation. In addition to OCD-triggers, aversive and neutral control stimuli were included. Both groups showed increased skin conductance and heart rate changes to aversive control stimuli, whereas only patients demonstrated augmented skin conductance responses to OCD-triggers. Overall ANS hyperarousal in patients relative to controls was found at trend level. Activity in limbic and paralimbic areas in OCD patients was increased to both generally aversive and OCD-relevant stimuli, whereas dorsolateral prefrontal cortex (DLPFC) hyperactivation, covarying with cardiac responses in patients but not in controls, was present for disorder-relevant triggers only. Despite the small study group, these preliminary findings suggest ANS hyperactivity during OCD symptom provocation that could reflect arousal to the perceived threatening value of OCD-triggers and might mediate elevated anxiety.     

癫癎患者发作间期心血管自主神经功能与心率变异性

目的　探讨癫　患者发作间期心血管自主神经功能与心率变异性（ＨＲＶ）的变化。方法　５１例癫　患者根据标准心血管自主神经功能试验结果分为阳性（ＡＮＦＴ＋）组及阴性（ＡＮＦＴ－）组,与正常对照组３６例对比,进行ＨＲＶ分析。结果　癫　患者发作间期心血管自主神经功能异常率为４５．１％,且病程越长异常率越高。癫　患者在ＨＲＶ时域分析及非线性定量分析指标上均较对照组降低,且以　ＡＮＦＴ＋组患者最明显。ＨＲＶ直方图、散点图亦有特征性改变,以ＡＮＦＴ＋组患者最为显著。结论　癫　患者发作间期心血管自主神经功能存在紊乱现象,这种现象可能与癫　患者的猝死发生有关,ＨＲＶ是测定这一变化的敏感方法。     

Levodopa, bromocriptine and selegiline modify cardiovascular responses in Parkinson's disease

Autonomic nervous system (ANS) involvement is frequently found in Parkinson's disease (PD), but its causal relationship to the disease itself and its medication is unclear. We evaluated the effects of PD medications on cardiovascular ANS functions. Heart rate (HR) responses to normal and deep breathing, the Valsalva manoeuvre and tilting, and blood pressure (BP) responses to tilting and isometric work were measured prospectively in 60 untreated PD patients randomised to receive either levodopa (n=20), bromocriptine (n=20) or selegiline (n=20) as their initial treatment. The results were compared with those of 28 healthy controls. The responses were recorded at baseline, after 6 months on medication and following a 6-week washout period. At baseline HR responses to normal breathing, deep breathing and tilting were already lower and the fall in the systolic BP immediately and at 5 min after tilting was more pronounced in the PD patients than in the controls. Six months' levodopa treatment diminished the systolic BP fall after tilting when compared to baseline, whereas bromocriptine and selegiline increased the fall in systolic BP after tilting and selegiline diminished the BP responses to isometric work. The BP responses returned to the baseline values during the washout period. The drugs induced no change in the HR responses. Thus PD itself causes autonomic dysfunction leading to abnormalities in HR and BP regulation and the PD medications seem to modify ANS responses further. Bromocriptine and selegiline, in contrast to levodopa, increase the orthostatic BP fall and supress the BP response to isometric exercise reflecting mainly impairment of the sympathetic regulation. Received: 17 February 2000 / Received in revised form: 25 May 2000 / Accepted: 15 June 2000     

Sympathetic and parasympathetic activity in cancer-related fatigue: more evidence for a physiological substrate in cancer survivors

Fatigue is a notable clinical problem in cancer survivors, and understanding its pathophysiology is important. This study evaluated relationships between fatigue and both sympathetic and parasympathetic nervous system activity in breast cancer survivors. Norepinephrine and heart rate variability (HRV) were evaluated at rest, as well as during and after a standardized laboratory speech and mental arithmetic stressor. The participants, 109 women who had completed treatment for stage 0-IIIA breast cancer within the past two years, were at least two months post surgery, radiation or chemotherapy, whichever occurred last. Women who reported more fatigue had significantly higher norepinephrine and lower HRV before and after the stressor than their less fatigued counterparts. Fatigue was not related to treatment or disease variables including treatment type, cancer stage, time since diagnosis, and time since treatment. Importantly, the relationship between HRV and cancer-related fatigue was sizeable. Based on research that has demonstrated characteristic age-related HRV decrements, our findings suggest a 20-year difference between fatigued and non-fatigued cancer survivors, raising the possibility that fatigue may signify accelerated aging. Furthermore, lower HRV and elevated norepinephrine have been associated with a number of adverse health outcomes; accordingly, fatigue may also signal the need for increased vigilance to other health threats.     

偏头痛患者的自主神经功能及其定量测定

用心率变异频谱分析定量测定６５例偏头痛患者和５０例健康人仰卧位和站立位自主神经系统功能。结果发现，偏头痛患者站立位中频段积分较对照组显著降低（Ｐ〈０．００１），表明其交感神经功能低下，且随着疼痛程度的增加及病程的延长，其交感神经功能低下的程度迹越重，本文还初步探讨了其机理及临床应用意义。     

Nutritionally-induced changes in parasympathetic function

It is possible to quantify the input of the parasympathetic nervous system to heart rate variability in man by the spectral analysis of heart rate variability. This is done by noninvasive, computerized electrocardiography over several minutes of observation. Earlier studies from this laboratory demonstrated that when body weight of obese or nonobese subjects is increased 10% or decreased below usual body weight, there are accompanying changes in autonomic function, as measured by alterations in heart rate variability. The clearest of these changes is an abrupt decline in parasympathetic function with increase in body weight, and an increase in parasympathetic activity as body weight declines, and when new, lower body weights are maintained. Recently, it has been possible to examine this phenomenon by a pharmacologic dissection of the autonomic input to heart rate variability. The separate input of each branch of the nervous system to cardiac variability, as well as the intrinsic heart rate, is measured by this approach. The subjects studied to date have been few, but there is confirmation of a major change in parasympathetic function with weight alteration whereas sympathetic changes are small.     

Heart rate variability during static and dynamic breath-hold dives in elite divers

The purpose of this study was to assess the differences in cardiac autonomic modulation during maximal static (SA) and dynamic (DA) underwater apneas. Arterial oxygen saturation (SpO(2)), heart rate (HR) and HR variability (SD1 from Poincaré plot and short-term fractal-like scaling exponent, α(1)) were analyzed at the immersed baseline (3 min) and initial, mid- and end-phases (each 30s) of SA and DA in nine elite breath-hold divers. DA and SA lasted 78 ± 8 and 225 ± 20s (mean ± SEM), respectively, and resulted in similar decrements in end-stage SpO(2) (78 ± 3 and 75 ± 3%, p=0.352). During DA, initial increase in HR (from 80 ± 5 to 122 ± 5 bpm, p<0.001) was followed by gradual decrease towards the baseline at mid-apnea and end-apnea phase (101 ± 6 and 80 ± 8 bpm, respectively). During SA, HR decreased at mid-apnea (from 78 ± 4 to 66 ± 3 bpm, p=0.004) but did not decrease further at end-apnea phase (66 ± 4b pm). Decreased SD1 was observed at the initial phase of DA (from 28 ± 5 to 10 ± 4 ms, p=0.005) being lower compared with SA (24 ± 4 ms, p=0.005). At the end of DA and SA, SD1 tended to increase above the baseline (62 ± 16 and 66 ± 10 ms, p=0.128 and p=0.093, respectively, p=0.602 DA vs. SA). α(1) tended to be higher at the end of DA compared with SA (1.17 ± 0.10 vs. 0.79 ± 0.10, p=0.059). We concluded that apnea blunts the effects of exercise on cardiac vagal activity at the end of DA. However, higher HR during DA compared with SA indicates larger cardiac sympathetic activity during DA, as suggested also by slightly higher α(1).     

脑梗死后心率变异的常见临床因素分析

目的 研究脑梗死患者心率变异性(HRV)的特点及其影响因素,为脑梗死的治疗提供有意义的借鉴.方法 研究梅州市人民医院神经内科自2007年5月至2009年6月收治、经CT或MRI检查确诊的190例脑梗死患者的临床资料,以同期健康体检者50例做为对照,利用24 hHRV分析技术测定并比较心脏自主神经活性受损程度,再按照脑梗死患者的年龄、性别、梗死类型、病情程度、预后、梗死部位对病例进行分组并分析上述因素对患者HRV的影响.结果 脑梗死组患者HRV相关指标均低于对照组;≥60岁组患者HRV各项指标低于<60岁组;除总功率谱(TF)外,女性HRV指标均低于男性,腔隙性梗死患者HRV指标高于动脉粥样硬化性腩梗死和脑栓塞患者,GCS评分较低的患者HRV指标较低,预后为死亡的患者HRV指标最低,其次为好转、治愈患者.右岛叶梗死患者HRV时域指标低于其他梗死部位患者,差异均有统计学意义(P<0.05).结论 脑梗死患者自主神经系统失衡,早期动态监测HRV可以判断脑梗死患者脑功能损伤程度及病情演变趋势,有助于早期识别高危患者,指导临床治疗.     

Sympathetic and parasympathetic pupillary dysfunction in familial dysautonomia

Objective assessment of autonomic dysfunction in familial dysautonomia (FD) is largely based on the analysis of cardiovascular responses to challenge maneuvers such as orthostatic stress. Infrared pupillometry (IPM) provides an additional reliable method for cranial autonomic evaluation and has the advantage of requiring minimal cooperation.This study was performed to determine whether IPM contributes to the assessment of autonomic function in FD patients.In 14 FD patients and 14 healthy controls, we studied absolute and relative light reflex amplitude, pupillary constriction velocity (v(constr)), pupillary diameter, early and late pupillary re-dilatation velocity (v(dil 1), v(dil 2)) after dark adaptation. Prior to IPM, all patients had an ophthamological examination to evaluate refraction and corneal integrity.In comparison to controls, patients had a significant reduction of the parameters reflecting parasympathetic pupillary function (absolute light reflex amplitude 1.34 +/- 0.21 vs. l.86 +/- 0.14 mm, relative light reflex amplitude 22.74 +/- 7.11% vs. 30.76 +/- 3.57%, v(constr) 3.75 +/- 1.09 vs. 5.80 +/- 0.59 mm/s) and of the parameters reflecting sympathetic pupillary function (diameter 5.69 +/- 0.66 vs. 6.35 +/- 0.60 mm, v(dil 1) 1.29 +/- 0.23 vs. 1.95 +/- 0.23 mm/s, v(dil 2) 0.64 +/- 0.13 vs. 0.72 +/- 0.l2 mm/s; Mann-Whitney U-test: p<0.05).The non-invasive technique of IPM demonstrates dysfunction not only of the cranial parasympathetic, but also of the cranial sympathetic nervous system and, thus, further characterizes autonomic dysfunction in FD.     

Autonomic function in narcolepsy: power spectrum analysis of heart rate variability

Ten narcoleptic patients that had never been treated previously and ten healthy volunteers of comparable age underwent 48-h polygraphic recording to assess the effects of wakefulness and sleep on beat-to-beat heart rate variability by means of power spectrum analysis. The study revealed decreased power in the low frequencies (LF) during sleep (whereby an increase of the power in this band is associated with sympathetic activation) compared with wakefulness, with minimal values during stage 3–4 non-REM sleep and higher levels during REM sleep, both in patients and controls. Significantly reduced power in high frequencies (HF; mainly expression of parasympathetic control) and a significantly increased LF/HF ratio during wakefulness before sleep in narcoleptics compared with controls were found. Our study excludes a primary disturbance of cardiac autonomic nervous system in narcoleptics but suggests an altered circadian autonomic function in these patients. Received: 23 May 1996 Received in revised form: 3 December 1996 Accepted: 17 January 1997     

Impairment of parasympathetic baroreflex responses in migraine patients

OBJECTIVES: The aim of this study was to assess baroreflex regulation of the heart rate and blood vessels in migraine patients in comparison with healthy controls. METHODS: In 30 migraine patients who were in a headache-free phase, aged 34 +/- 2 years, and 30 healthy controls, aged 34 +/- 3 years, we applied oscillatory neck suction at 0.1 Hz to assess the sympathetic modulation of the heart and blood vessels and at 0.2 Hz to assess the effect of parasympathetic stimulation on the heart. Breathing was paced at 0.25 Hz. Electrocardiographic RR-intervals, blood pressure and respiration were continuously recorded. Responses to the baroreflex stimulations were assessed as the changes in power of the RR-interval and blood pressure fluctuations at the relevant stimulating frequency from the baseline values. RESULTS: Systolic and diastolic blood pressure responses to the 0.1 Hz neck suction pressure were not significantly different between the patients and controls. The RR-interval oscillatory response to 0.2 Hz neck suction was significantly less (P < 0.05) in the migraine patients (4.45 +/- 0.27 ln ms2) compared with the controls (5.48 +/- 0.36 ln ms2). CONCLUSION: These results suggest that baroreflex-mediated cardiovagal responses are reduced in migraine patients. However, the sympathetic-mediated baroreflex control of the blood vessels is intact in the migraine patients. The autonomic nervous system may have a role in the pathophysiology of migraine.     

Interictal cardiovascular autonomic responses in patients with temporal lobe epilepsy

PURPOSE: To measure interictal cardiovascular autonomic functions in patients with either refractory or well-controlled temporal lobe epilepsy (TLE). METHODS: For autonomic assessment, heart rate variation during normal and deep breathing, Valsalva maneuver, and tilting were measured in 19 patients with chronic refractory TLE, 19 patients with well-controlled TLE, and 38 age- and sex-matched healthy control subjects. Blood pressure responses to tilting and isometric work also were evaluated. RESULTS: Heart-rate (HR) variation during normal breathing (p = 0.006) and tilting (p = 0.043) was lower in patients with refractory TLE than in control subjects. Heart-rate response to tilting (p = 0.036) was also lower in patients with well-controlled TLE than in control subjects. Blood-pressure responses showed no differences between the patients and the control subjects. Patients taking carbamazepine (CBZ) medication had decreased HR responses to deep breathing (p = 0.046) and to tilting (p = 0.014) compared with the control subjects. CONCLUSIONS: Refractory TLE seems to be associated with dysfunction of the cardiovascular autonomic regulation, manifesting as impaired HR responses to certain stimuli. Interictal autonomic dysfunction is seen in patients with well-controlled TLE as well, but it may be more evident in patients with refractory epilepsy. CBZ medication may also be associated with altered autonomic cardiac control.     

Heart rate variability and cardiac arrhythmias in patients with chronic renal failure

Heart rate variability was measured from 24-h electrocardiograms in 61 patients with end stage chronic renal failure. The method used counts the number of times successive RR intervals differ by more than 50 ms over the 24-h period, and is a reliable indicator of cardiac parasympathetic activity. Also analysed were the frequency and type of ectopic beats and other arrhythmias. Twentyone subjects (34%) had varying numbers of ventricular ectopic beats, and twelve (20%) had frequent supraventricular ectopics. Total 24-h count values were abnormal in 30 (76%) of the 41 subjects whose tapes were technically suitable for this analysis. There were no sex differences, but those patients maintained on haemodialysis had significantly lower counts than those on continuous ambulatory peritoneal dialysis. We conclude that about three-quarters of patients with chronic renal failure have abnormal cardiac parasympathetic activity. This may increase susceptibility to cardiac arrhythmias and sudden death and contribute to the high mortality of patients with chronic renal failure.     

Intranasal oxytocin enhances emotion recognition from dynamic facial expressions and leaves eye-gaze unaffected

Previous studies have shown that oxytocin improves the encoding and recognition of facial expressions, which has been proposed to be mediated by an increased exploration of the eye region during face processing. In the present study, we used eye tracking to assess visual attention to the eye region while participants performed a dynamic facial emotion recognition task. In a double-blind, placebo-controlled between-subjects design participants received 24 IU intranasal oxytocin (n = 23) or a placebo (n = 24). Although oxytocin administration had no effect on participants' visual scanning of emotional faces, it generally enhanced recognition performance, as the oxytocin group recognized emotional expressions at lower intensity levels. These findings suggest that oxytocin-induced improvement of facial emotion recognition is independent of modulations in overt visual attention.     

Relationship between frequency spectrum of heart rate variability and autonomic nervous activities during sleep in newborns

Introduction

We analyzed the frequency spectrum of two neonatal sleep stages, namely active sleep and quiet sleep, and the relationship between these sleep stages and autonomic nervous activity in 74 newborns and 16 adults as a comparison.