倍他洛克对心脏自主神经系统的影响

目的 :研究倍他洛克对心脏自主神经系统的影响。方法 :用我室研制的计算机分析系统 ,测定自愿受试者在给予倍他洛克(50mg,口服 )前和后3小时的心动周期信号的特征参数。结果 :倍他洛克能使心动周期、心动周期的标准差、谱的总功率、谱的高频成分显著增加 ,心率和谱的超低频成分的相对值 (Rpu)显著降低。结论 :(1)倍他洛克能使心动周期的标准差 (或心率的标准差 )增加 ,是使心动周期信号 (HPS)谱的高频成分显著增加的根本原因 ,也是副交感神经的张力增加的根本原因 ;(2)倍他洛克表现出降低心脏交感神经的张力 ,增加心脏副交感神经的张力 ,增加心脏自主神经系统的张力。     

培哚普利对充血性心力衰竭患者心率变异性的影响

目的:观察培哚普利对充血性心力衰竭(congestive heartfailure,CHF)心率变异性(heart rate variability,HRV)的影响,以探讨培哚普利治疗CHF的可能机制.方法:选择24例CHF患者,测量治疗前后HRV各项指标的变化,并与22名健康志愿者进行对照.结果:治疗前CHF患者HRV所有成分除低频功率(LF)/高频功率(HF)外较正常对照者均显著下降(P＜0.001).治疗后培哚普利组正常R-R间期的标准差(SDNN)、节段平均R-R间期的标准差(SDANN)、总功率(TP)、极低频功率(VLF)、LF、HF增加非常显著(P＜0.01),相邻R-R间期差值的均方根(RMSSD)显著增加(P＜0.05),而标准差的平均值(SDNNindex)、相邻R-R间期差值大于50 ms记数占总R-R间期数的百分比(PNN50)有增加趋势,但无统计学意义(P＞0.05);LF/HF有减小趋势,无统计学意义(P＞0.05).结论:培哚普利可以改善心脏自主神经功能的失衡,其作用机制可能与降低交感神经张力、增加迷走神经张力有关.     

红霉素对大鼠心率变异性的影响

目的以心率功率谱为指标探讨红霉素（erythromycin，EM）对心脏自主神经系统活性的影响。方法32只SD成年大鼠随机分为生理盐水组和红霉素25、50及100mg／kg共四组，利用心率变异性（heart rate variability，HRV）分析方法观察静脉注射红霉素前、后SD大鼠HRV各参数的变化。结果生理盐水组、红霉素25mg／kg组注射前、后各参数值无显著性变化。红霉素100mg／kg组注射红霉素后平均心动周期（Mhp）、超低频功率（APU）、高频功率（APH）、总功率谱（TPV）、超低频功率／高频功率（RUN）、相对分散度（Hrd），分维数（Hfd）明显升高；混沌度（Hcc）、平均心率（Mhr）明显降低，变化幅度随剂量增大而增加，峰值提前。不同剂量组间有显著性差异。结论静脉注射大剂量红霉素心脏自主神经系统稳定性下降，交感与副交感间平衡失调。     

氯沙坦对高血压病患者心率变异性影响的研究

目的 :探讨氯沙坦对高血压病患者心率变异性的影响。方法 :分别对50例健康查体者及90例高血压病患者口服氯沙坦治疗前、后行24小时动态心电图检查 ,分析心率功率谱时域和频域指标。结果 :高血压病患者用药前和用药后相邻正常RR间期标准差(SDNN )、RR间期平均值的标准差 (SDANN )、高频功率和总功率、低频功率、低频功率/高频功率值分别显著低于和高于正常对照组 ,高血压病患者治疗前、后上述指标亦呈显著变化。Ⅲ期高血压病患者的SDNN、高频功率、低频功率及低频功率/高频功率值与Ⅱ期高血压病患者比较 ,P<0 05 ;Ⅱ期高血压病患者的SDNN、高频功率、低频功率及低频功率/高频功率值与Ⅰ期高血压病患者比较 ,P<0 05 ,显示植物神经功能损害与病情呈正相关。各期高血压病患者在经氯沙坦治疗后血压有效下降的同时 ,心率变异性损害均有改善。结论 :氯沙坦在降压治疗的同时 ,可改善高血压病患者的心率变异性     

依那普利对原发性高血压患者心率变异性的影响与临床研究

目的探讨依那普利对原发性高血压患者心率变异性的影响与临床意义。方法对100例健康查体者行24 h动态心电图作为正常对照组,比较150例原发性高血压患者服依那普利前后做24 h动态心电图,分析心率功率谱时域和频域指标。结果原发性高血压患者低频和总频显著增加,低频与高频比值增大,高频减少。时域相邻正常R-R间期标准差(SDNN)和R-R间期平均值的标准差(SDNN)明显下降,与正常对照组比较均有显著性差异。原发性高血压患者的昼夜变化差异也较正常对照组显著下降。经依那普利治疗后,除有效降压外,患者的SDNN、SDANN和高频增加,总频、低频、低频与高频比值减小,与对照组和治疗前比较均有显著性差异,其昼夜变化规律亦显著部分恢复。结论依那普利在降压的同时,可改善原发性高血压患者的心率变异性。     

无症状先天性心脏病患者的心率变异性

目的 :研究无症状先天性心脏病 (ACHD)患者的心率变异性。方法 :应用 2 4 h动态心电图测定 2 0例 ACHD患者 (研究组 )和 2 0例正常人 (对照组 )的心率和心率变异频域指标。结果 :研究组 2 4 h最慢心率、最快心率、平均心率与对照组无显著性差异 ,但总功率谱密度、高频成分和低频成分均低于正常对照组。结论 :ACHD患者的心率在正常范围时 ,心率变异性已经减低。     

培哚普利对充血性心力衰竭患者心率变异性的影响

目的：观察培哚普利对充血性心力衰竭（congestive heartfailure,CHF）心率变异性（heart rate variability,HRV）的影响,以探讨培哚普利治疗CHF的可能机制.方法：选择24例CHF患者,测量治疗前后HRV各项指标的变化,并与22名健康志愿者进行对照.结果：治疗前CHF患者HRV所有成分除低频功率（LF）/高频功率（HF）外较正常对照者均显著下降（P＜0.001）.治疗后培哚普利组正常R-R间期的标准差（SDNN）、节段平均R-R间期的标准差（SDANN）、总功率（TP）、极低频功率（VLF）、LF、HF增加非常显著（P＜0.01）,相邻R-R间期差值的均方根（RMSSD）显著增加（P＜0.05）,而标准差的平均值（SDNNindex）、相邻R-R间期差值大于50 ms记数占总R-R间期数的百分比（PNN50）有增加趋势,但无统计学意义（P＞0.05）;LF/HF有减小趋势,无统计学意义（P＞0.05）.结论：培哚普利可以改善心脏自主神经功能的失衡,其作用机制可能与降低交感神经张力、增加迷走神经张力有关.     

培哚普利对2型糖尿病合并心脑血管疾病心率变异性的影响

目的　研究血管紧张素转换酶抑制剂培哚普利 (perindopril)对 2型糖尿病合并心脑血管疾病患者心率变异性 (heart rate variability,HRV)的影响。方法　 35例 2型糖尿病合并心脑血管疾病者服培哚普利 (4～6 mg/ d,8周 ) ,前后行 2 4 h动态心电图检查 ,分析心率功率谱时域和频域指标。结果　培哚普利使 HRV时域指标正常 RR间期的标准差 (SDNN)、每连续 5 min时段标准差 (SDANN) ,相邻 RR间期之差的均方根值 (r MSSD)和频域指标高频 (HF)显著增加 ,频域指标总频谱 (TF) ,低频 (L F)和 L F/ HF明显降低。结论　培哚普利对糖尿病合并心脑血管疾病患者心率变异性产生有益的作用 ,并对预防心脑血管疾病再发有重要意义     

直立倾斜试验中心率功率谱密度变化

50例不明原因晕厥病人及15例正常人行直立倾斜试验（HUT）．检查同时作心率功率谱密度（HRPSD）分析。结果示倾斜前5分钟及倾斜后5分钟总功率谱（T）、超低频（VLF）、低频（LF）、高频（HF）段功率谱密度以及低／高频比（LF／HF）及其变化在阳性、阴性和对照组均相似（P＞0．05）。检查结束前5分钟，阳性组T、VLF、LF、LF／HF又有显著增加．而阴性、对照组无明显变化，阳性与阴性、对照组有显著差异（P＜0．01）。表明阳性组晕厥发作前有交感神经系统活性的异常增加以及交感、副交感神经平衡功能失常。     

吲达帕胺对高血压病患者心率变异性影响的研究

目的：探讨吲达帕胺对高血压病患者心率变异性的影响。方法：对90例高血压病患者口服吲达帕胺治疗前后行24小时动态心电图检查,分析心率功率谱时域和频域指标,另设50例健康查体者为对照组。结果：高血压病患者用药前和用药后相邻正常RR间期标准差（SDNN）,RR间期平均值的标准差（SDANN）,高频功率和总功率,低频功率,低频功率／高频功率值分别显著低于和高于正常对照组,高血压病患者治疗前后上述指标亦呈显著变化,高血压病患者经吲达帕胺治疗后血压有效下降的同时,心率变异性损害有所改善。结论：吲达帕胺在降压治疗的同时,可改善高血压病患者的心率变异性。     

Power Spectral Analysis of Heart Rate Variability in Rats as a Quantitative Tool in the PK-PD Analysis of the Parasympatholytic Activity of Atropine

Purpose. To utilize power spectral analysis (PSA) of heart rate variability (HRV) as a pharmacodynamic (PD) measure of atropine parasympathetic effect, and to model the kinetics of action. Methods. Heart rate data was collected following atropine administration to rats and was analyzed off-line for high frequency peaks by PSA of HRV as a measure of parasympathetic tone. A temporal cumulative approach (TCA) detected transient changes in parasympathetic activity. The pharmacokinetics (PK) was analyzed and linked to both direct and indirect PK-PD models. Results. TCA enabled a quantitative measure of atropine parasympathetic activity. A simultaneous fit of the indirect PK-PD model to the experimental data of all three atropine doses successfully captured the experimental data. Conclusions. TCA can be used as a quantitative measure of parasympathetic tone. Our work has established a preclinical model to investigate the kinetics of drug action on the autonomic nervous system.     

糖尿病患者心率变异的研究

对30例2型糖尿病患者,25例对照者进行了心率变异性（HRV）的检测。结果表明：糖尿病患者中存在明显的HRV异常,其平均心率增快,平均R－R间期、平均R－R间期标准差、平均R－R间期变异系数及R－R间期大于50ms百分率均明显降低;心率能谱分析中,低频断和高频断的能量均降低,总的趋向是交感神经活动增强．迷走神经作用减弱。表明糖尿病患者HRV变小,自主神经系统活动及心血管系统功能异常。HRV为监测糖尿病患者植物神经功能动态改变提供了一种新的手段。     

Role of the parasympathetic nervous system and interaction with the sympathetic nervous system in the early phase of hypertension

The role of the peripheral parasympathetic nervous system in the development of hypertension was investigated in spontaneously hypertensive rats (SHR) and Wistar-Kyoto (WKY) rats. Animals were 5-7 weeks old, anesthetized, and in the open-chest condition. The decrement in heart rate evoked by parasympathetic nerve stimulation (62 +/- 8 beats/min) in SHR was greater (p < 0.01) than that in WKY rats (23 +/- 4 beats/min). Furthermore, the decrease in heart rate (73 +/- 9 beats/min) in response to combined stimulation of sympathetic and parasympathetic nerves in SHR was greater (p < 0.05) than that in response to vagal stimulation alone. The extent of the interaction of sympathetic and parasympathetic nerves was calculated as the difference between the decrease in heart rate during combined stimulation and that during vagal nerve stimulation alone. The extent of the interaction in SHR (-11 +/- 5) was not significantly different from that in WKY rats (-8 +/- 3 beats/min). Therefore, the influence of the peripheral parasympathetic nervous system in the early phase of hypertension may be greater than that in the normotensive state. Interaction between the two branches of the autonomic nervous system may occur as accentuated antagonism originating in the early phase of hypertension. The interaction during the early phase of hypertension may not be different in extent from that of the normotensive state.     

Effects of Cacao Liquor Polyphenols on Cardiovascular and Autonomic Nervous Functions in Hypercholesterolaemic Rabbits

Abstract: Many epidemiological studies have shown that polyphenols can reduce the risk of mortality from cardiovascular diseases. This study tested the hypothesis that cacao liquor polyphenols have the properties to restore the cardiovascular and autonomic nervous function in an animal model of familial hypercholesterolaemia. Male Kurosawa and Kusanagi‐hypercholesterolaemic rabbits were housed in individual cages in a room where a 12‐hr light:dark cycle (lights‐on at 8:00 and lights‐off at 20:00) was maintained. At 3 months of age, they were divided into two groups (standard diet and cacao liquor polyphenol) and the animals received 100 g of the respective diets per day and were provided with tap water ad libitum. Heart rate and blood pressure were measured by a telemetry system. To clarify the autonomic nervous function, power spectral analysis of heart rate variability, baroreflex sensitivity and autonomic nervous tone were measured. After 6 months of dietary administration of cacao liquor polyphenols, heart rate and blood pressure were lowered but plasma lipid concentrations were unchanged. The area of atherosclerotic lesions in the aorta in the cacao liquor polyphenol group was significantly smaller than that in the standard diet group. The high‐frequency power of heart rate variability in the rabbits in the standard diet group was significantly decreased with ageing, but that in the cacao liquor polyphenol group was not different between short‐term and long‐term treatment. Moreover, cacao liquor polyphenols preserved parasympathetic nervous tone, although that in the standard diet group was significantly decreased with ageing. We conclude that cacao liquor polyphenols may play an important role to protect cardiovascular and autonomic nervous functions.     

REDUCED DIETARY FAT INTAKE INCREASES PARASYMPATHETIC ACTIVITY IN HEALTHY PREMENOPAUSAL WOMEN

1. Hypercholesterolaemia has been associated with decreased heart rate variability, a measure of cardiac parasympathetic activity. However, the effect of perturbation of the lipid profile on autonomic function has not been examined systematically. 2. The effects of short-term dietary lipid modification on autonomic function are studied in 25 normotensive, non-smoking, premenopausal women with normal bodyweight. Subjects consumed either a low (L, 25%) or high fat (H, 40%) diet for 2 weeks in an open, randomized, cross-over manner with a 2 week washout. 3. Baroreflex sensitivity was determined by gating beat-to-beat heart period (RR) interval and continuous non-invasive blood pressure recordings. Heart rate variability measures of cardiac parasympathetic nervous system activity were obtained in the time (standard deviation of RR intervals, root mean square of successive differences (rMSSD)) and frequency (high frequency power) domains. All assessments were made at the same timepoint in the menstrual cycle. 4. Both low-density lipoprotein-cholesterol and high-density lipoprotein-cholesterol decreased significantly (P < 0.05) with increased dietary fat intake (H, 2.7 +/- 0.1 vs L, 2.2 +/- 0.1; H, 1.3 +/- 0.1 vs L, 1.1 +/- 0.1 mmol/L, respectively) as did mean arterial pressure (H, 78.1 +/- 1.5 vs L, 74.3 +/- 1.5 mmHg). Weight was unchanged by dietary lipid intake (H, 62.6 +/- 8.5 vs L, 62.3 +/- 8.3 kg, P = NS). 5. There was a significant increase in rMSSD (H, 29.6 +/- 3.4 vs L, 38.8 +/- 6.4 msec, P < 0.05) and natural logarithm of high frequency power following low fat diet (H, 4.4 +/- 0.2 vs L, 4.8 +/- 0.3 msec2, P = 0.01). Baroreflex sensitivity also increased following the low fat diet (H, 13.91 +/- 2.2 vs L, 16.9 +/- 3.2 msec/mmHg, P = 0.23). 6. Short-term dietary lipid modification can significantly increase cardiac parasympathetic nervous system activity in healthy premenopausal women. These changes in autonomic status appear to be independent of changes in bodyweight and may be of clinical relevance considering the prognostic implications of heart rate variability in cardiovascular disease.     

Involvement of the Autonomic Nervous System in Diurnal Variation of Corrected QT Intervals in Common Marmosets

Our previous study has shown that the corrected QT (QTc) interval of the electrocardiogram is longer during the dark period than during the light period in telemetered common marmosets. In the present study, we investigated the involvement of sympathetic and parasympathetic nervous activities in the changes of QTc interval associated with the light–dark cycle. Telemetry transmitters were implanted in six common marmosets to continuously record the electrocardiogram. The QT intervals obtained were corrected for the RR interval by applying individual probabilistic QT-rate correction formulae. Power spectral analysis of heart rate variability was performed to quantify each autonomic nervous function. Changes in QTc intervals and autonomic nervous tones were associated with the light–dark cycle. Parasympathetic nervous activity and QTc intervals significantly increased by approximately 10 ms during the dark period. Atropine, a muscarinic receptor antagonist, suppressed the increased parasympathetic tone and QTc prolongation during the dark period. In contrast, propranolol, a β-adrenoceptor antagonist, decreased the sympathetic activity and increased QTc intervals during the light period. These results suggest that the parasympathetic nerve functions prolong QTc intervals during the dark period, while the sympathetic nerve functions shorten them during the light period in common marmosets.     

心肌缺血与交感神经传入的研究进展

心脏的自主神经包括交感神经与副交感神经。支配心脏的交感神经不仅有传出轴突,也有传递心脏感受的传入神经。心肌缺血可激活心交感传入神经并将信息传递到大脑心血管中枢,通过兴奋交感传出神经引起交感兴奋性反射,出现心率加快和血压升高等现象使心肌缺血、缺氧和心绞痛加重。因此,交感神经功能变化可加重心肌缺血损伤。     

Effects of atropine on the time and frequency domain estimates of blood pressure and heart rate variability in mice

1. Indices quantifying blood pressure (BP) and heart rate (HR) variability have been recently developed and may be used to assess the contribution of the autonomic nervous system to cardiovascular fluctuations. 2. Cardiovascular variables were measured in eight conscious mice equipped with a BP telemetric device. Each recording session was conducted when the mice were at rest and included a control period, an injection of atropine methylnitrate (2 mg/kg) and a post-treatment recording. 3. Time domain indices were the mean pulse interval (PI) and NN (the normal-to-normal intervals), mean HR, standard deviation of PI (SDNN), the square root of the mean of the sum of the squares of differences between adjacent PI (RMSSD) and the pNN8 (NN8 count divided by the number of NN intervals). Frequency domain indices of HR variability were the low frequency (LF) zone (0.15-0.60 Hz) and the high frequency (HF, respiratory sinus arrhythmia) zone (2.5-5.0 Hz) of the PI power spectrum. The time domain index of spontaneous baroreflex sensitivity (BRS) was the slope of the linear PI and systolic BP relationship obtained using the sequence technique. The frequency domain indices of BRS were the gain of the transfer function between systolic BP and PI in the LF and HF bands. 4. Atropine markedly affected these variables, illustrating vagal predominance under resting conditions in mice. The preferable time and frequency domain indices for quantifying the vagal contribution to HR variability were the pNN8 and the LF gain.     

Autonomic nervous system activity imbalance in cardiomyopathic hamster

There is strong evidence that autonomic imbalance plays an important role in progression of heart failure. Analysis of heart rate variability (HRV) has achieved substantial acceptance as a noninvasive method for the assessment of autonomic tone. The purpose of this investigation was to study HRV in an experimental model of heart failure using cardiomyopathic (BIO TO.2) hamsters. Animals showed an autonomic imbalance of cardiac control that seems due to attenuation of parasympathetic activity and an enhanced sympathetic tone. The reduction of parasympathetic activity in BIO TO.2 hamsters is suggested by (a) the reduction of the high-frequency (HF) spectrum, and (b) the lack of atropine to generate a response. The increased sympathetic activity is indicated by (a) the decreased time-domain indexes, (b) the increased LF/HF ratio of the power spectrum, and (c) the alteration of HRV indexes induced by propranolol. These results support the notion that in heart failure, there is a similar autonomic imbalance in both human and hamster and suggest that the cardiomyopathic hamster is a suitable experimental model for studying the involvement of the autonomic nervous system in the progression of heart failure.