迷走神经兴奋对HRV的影响及其机制的初步分析

实验在氯醛糖加氨基甲酸乙酯麻醉的新西兰兔上进行。记录血压、心率、心电图和心率变异性（ＨＲＶ）频谱分析。电刺激减压神经（ＤＮ）,疑核（ＮＡ）和右侧迷走神经（ＲＶ）外周端,均引起心率和血压下降（Ｐ＜０．００１）,总变异性（ＴＶ）、低频成分（ＬＦ）、高频成分（ＨＦ）、ＬＦ／ＨＦ比值（ＬＦ／ＨＦ）和极低频成分（ＶＬＦ）增大（Ｐ＜０．０５－０．００１）。静脉注射阿托品可使上述反应显著减小（Ｐ＜０．０５－０．０１）,而静脉注射心得安仅可阻断ＤＮ和ＮＡ所致ＬＦ的增大（Ｐ＜０．０５）。以上结果表明：迷走神经是ＨＲＶ的主要调节者之一;ＨＦ由迷走神经单独介导;ＬＦ受迷走神经和交感神经共同调制;迷走神经参与ＶＬＦ波的形成     

植物胚胎学实验方法（七）同时显示胚中贮藏的淀粉,蛋白质和脂类的永久制片法

植物胚胎学实验方法（七）同时显示胚中贮藏的淀粉、蛋白质和脂类的永久制片法胡适宜（北京大学生物系,北京１００８７１）ＭＥＴＨＯＤＯＦＰＲＥＰＡＲＡＴＩＯＮＯＦＳＬＩＤＥＳＦＯＲＳＩＭＵＬＡＮＥＯＵＳＤＥＭＯＮＳＴＲＡＴＩＯＮＳＯＦＳＴＡＲＣＨＧＲＡＩＮ...     

补体分子结构中的共有基序

在人补体系统３０多种成分中，约有一半左右的分子中含有某种共的有结构序列。目前已翻，这些基序有ＳＣＲ（ＣＣＰ），ＴＳＲ，ＥＧＦ前体，ＬＤＬ－Ｒ，ＦＩＭ，ＳＰ区等。在补体分子中，有的只含有一种基序，如ＲＣＡ分子只含有ＳＣＲ，Ｐ分子中只含有ＴＳＲ；有的含有多种基序，如Ｃ６，Ｃ７，Ｃ８及Ｃ９等。     

P物质在谷氨酸兴奋外侧下丘脑-穹窿周围区引起的升压反应中之作用

Ｐ物质（ＳＰ）能神经元及其轴突末梢和受体广泛分布于很多心血管中枢。外侧下丘脑含ＳＰ能神经元,外侧下丘脑投射的升压区内又存在ＳＰ能纤维及ＳＰ受体;因此本工作检验ＳＰ在外侧下丘脑升压反应中的作用。实验显示：（１）Ｌ－谷氨酸（Ｇｌｕ）兴奋外侧下丘脑的穹窿周围区（ＬＨ／ＰＦ）或将ＳＰ分别注入各ＬＨ投射区：蓝斑（ＬＣ）、臂旁核（ＮＰＢ）或中脑导水管周围灰质（ＰＡＧ）均引起升压反应;（２）［Ｄ－Ｐｒｏ２,Ｄ－Ｐｈｅ７,Ｄ－Ｔｒｐ９］－ＳＰ（ＳＰ拮抗剂）预先注入ＬＣ或ＰＡＧ可使Ｇｌｕ兴奋ＬＨ／ＰＦ引起的升压反应减小,而注入ＮＰＢ对该反应无明显影响;（３）双侧延髓头端腹外侧区（ＲＶＬ）分别用酚妥拉明、心得安或阿托品预处理也可明显削弱该反应。结合我们以往的实验结果：ＲＶＬ内的α－、β－、Ｍ－受体介导ＬＣ升压反应,α－和β－受体介导ＰＡＧ－升压反应;本工作显示ＬＨ／ＰＦ可通过其ＳＰ能投射纤维作用于ＬＣ－ＲＶＬ和ＰＡＧ－ＲＶＬ升压系统而实现其升压反应。     

东北鼢鼠种群生长指标的主分量分析

东北鼢鼠种群生长指标的主分量分析ＰＲＩＮＣＩＰＡＬＣＯＭＰＯＮＥＮＴＡＮＡＬＹＳＩＳＯＦＧＲＯＷＴＨＩＮＤＥＸＯＦＰＯＰＵＬＡＴＩＯＮＦＯＲＭＡＮＣＨＵＲＩＡＮＺＯＫＯＲ（ＭＹＯＰＡＬＡＸＰＳＩＬＵＲＡＳ）东北鼢鼠（Ｍｙｏｐａｌａｘｐｓｉｌｕｒａｓ...     

黑线姬鼠肥满度的研究

黑线姬鼠肥满度的研究ＳＴＵＤＹＯＮＴＨＥＲＥＬＡＴＩＶＥＦＡＴＮＥＳＳＯＦＴＨＥＳＴＲＩＰＥＤＦＩＥＬＤＭＯＵＳＥ（ＡＰＯＤＥＭＵＳＡＧＲＡＲＩＶＳ）ＫｅｙｗｏｒｄｓＳｔｒｉｐｅｄｆｉｅｌｄｍｏｕｓｅ（Ａｐｏｄｅｍｕｓ：ａｇｒａｒｉｕｓ）;Ｒｅｌａｔ...     

利用RFLP,SSR,AFLP和RAPD标记分析玉米自效系遗传多样性的比较研究

利用ＲＦＬＰ、ＳＳＲ、ＡＦＬＰ和ＲＡＰＤ４种分子标记方法研究了１５个玉米（Ｚｅａ ｍａｙｓ Ｌ．）自交系的遗传多样性,同时对４种标记系统进行比较。在供试材料中筛选到具多态性的ＲＦＬＰ探针酶组合５６个,６７６对ＳＳＲ引物,２０个ＲＡＰＤ引物和９个ＡＦＬＰ引物组合,分别检测到多态性带１６７、２０１、８７和１０８条。ＳＳＲ标记位点的平均多态性检测效率（Ａｉ,３２．２）。４种分子标记所得遗传相似自交系划分     

常绿阔叶林中种群在群落中地位测度指标的探讨

常绿阔叶林中种群在群落中地位测度指标的探讨方炜,彭少麟（中国科学院华南植物研究所,广州,５１０６５０）ＡＳＴＵＤＹＯＮＩＮＤＩＣＥＳＯＦＰＵＰＵＬＡＴＩＯＮＰＯＳＩＴＩＯＮＩＮＣＯＭＭＵＮＩＴＹＯＦＥＶＥＲＧＲＥＥＮＢＲＯＡＤＬＥＡＶＥＤＦＯＲＥＳＴ...     

孢粉药材及花类药材的孢粉形态研究

孢粉药材及花类药材的孢粉形态研究周日宝方石林１常劲罗友义（湖南中医学院中药系,长沙４１０００７）ＳＴＵＤＹＯＮＴＨＥＳＰＯＲＯ┐ＰＯＬＬＥＮＭＯＲＰＨＯＬＯＧＹＯＦＴＨＥＭＥＤＩＣＩＮＡＬＳＰＯＲＥＳ,ＰＯＬＬＥＮＳＡＮＤＦＬＯＷＥＲＳＺｈｏｕＲｉ...     

中国革螨二新纪录种（蜱螨亚纲：厉螨科、巨螫螨科）

中国革螨二新纪录种（蜱螨亚纲：厉螨科、巨螫螨科）ＴＷＯＮＥＷＬＹＲＥＣＯＲＤＥＤＳＰＥＣＩＥＳＯＦＧＡＭＡＳＩＮＡＦＲＯＭＣＨＩＮＡ（ＡＣＡＲＩ：ＬＡＥＬＡＰＩＤＡＥ,ＭＡＣＲＯＣＨＥＬＩＤＡＥ）￥ＹＥＲＵＩ－ＹＵ（ＸｉｎｊｉａｎｇＩｎｓｔｉｔｕｔｅ...     

迷走神经兴奋性对HRV的影响及其机制的初步分析

实验在氯醛糖加氨基甲酸乙酯麻醉的新西兰兔上进行。记录血压,心率,心电图和心率变异性频谱分析。电刺激减压神经,疑核和右侧迷走神经外周端,均引起心率和血压下降,总变异性,低频成分,高频成分,ＬＦ／ＨＦ比值和极代频成分增大。静脉注射阿托品可使上述反应显著减小,而静脉注射心得安仅可阻断ＤＮ和ＮＡ所致ＬＦ的增大。     

摄食行为对小型猪心脏自主神经功能的影响

目的观察摄食行为对小型猪心脏自主神经功能的影响。方法利用大动物无创遥测技术观察清醒活动状态下小型猪摄食前（BI）、摄食过程中（IP）、摄食后（AI）、AI 2 h和AI 4h的心电图（ECG）和自主活动,并用HRV功率谱分析其自主神经功能。结果与摄食前比较,小型猪摄食过程中心率（HR）、自主活动和标准化低频成分（LFnu）明显增加,RR间期（RRI）、总功率（TP）、极低频成分（VLF）、高频成分（HF）明显减少,LF/HF比值明显升高;且随着摄食后恢复时间的延长,小型猪HR、自主活动、LFnu均有所降低,而RRI、TP、VLF、HF均有所升高,LF/HF比值逐渐降低,并在摄食后2 h、4 h时变化显著;相关分析显示摄食行为与TP、VLF、HF、LF和LF/HF密切相关,多元线性逐步回归分析亦显示摄食行为与VLF、LF/HF和TP密切相关,且VLF起主要作用。结论小型猪摄食行为不仅影响心脏活动;而且能引起小型猪心脏自主神经控制能力发生改变,其中VLF在摄食行为过程中占有重要作用。     

Power spectral analysis of heart rate variability for assessment of diurnal variation of autonomic nervous activity in miniature swine.

BACKGROUND AND PURPOSES: The purpose of the study was to document diurnal variation of autonomic nervous functions by use of power spectral analysis of heart rate (HR) variability. METHODS: To clarify characteristics of power spectral analysis of HR variability, electrocardiogram (ECG), blood pressure (BP), and respiratory (Resp) waveform simultaneously were recorded. RESULTS: Two major spectral components were examined at low (LF)- and high (HF)-frequency bands for HR variability. Coherence between HR and Resp variabilities and HR and BP variabilities was maximal at approximately 0.14 and 0.03 Hz, respectively. On the basis of these data, two frequency bands of interest--LF (0.01 to 0.07 Hz) and HF (0.07 to 1.0 Hz)--were defined. Autonomic blockade studies indicated that the parasympathetic system mediated the HF and LF components, whereas the sympathetic system mediated only the LF component; HR had a diurnal pattern. The LF and HF bands in the dark phase tended to be higher than those in the light phase. The LF-to-HF ratio had a diurnal pattern similar to that of the HR. CONCLUSION: Parasympathetic nervous activity in miniature swine may be predominant in the dark phase. The characteristics of power spectra and diurnal variations of autonomic nervous functions are almost the same as those of humans. Therefore, miniature swine may be a useful animal model for future biobehavioral and pharmacotoxicologic studies.     

The nature of very low frequency component of the heart rate variability and the role of sympathetic-parasympathetic interactions

A method of separate monitoring "instant" changes of the VLF, LF and HF power spectral components of heart rate variability, has been developed. The power of the LF and HF spectral components were proved to be continuously changing. The period of these power fluctuations could stay within 15 to 150 sec. Comparison of the heart rate variability spectrum with LF and HF spectral components power fluctuations' spectrums has shown that the frequencies of the LF and HF spectral components power fluctuations stay within the VLF range. The co-operative spectrum form of these fluctuations repeats the form of the VLF peak. In cases when the LF and HF spectral components power fluctuations' periods do not coincide, VLF has two peaks. The frequency of one VLF peak coincides with frequency of the HF power fluctuations, and the frequency of another--with the frequency of LF power fluctuations.     

Time–frequency analysis of variabilities of heart rate, systolic blood pressure and pulse transit time before and after exercise using the recursive autoregressive model

Time–frequency (T–F) analysis is often used to study the non-stationary cardiovascular oscillations such as heart rate and blood pressure variabilities in dynamic situations. This study intends to use the T–F recursive autoregressive technique to investigate variability in pulse transit time (PTT), which is a cardiovascular parameter of emerging interest due to its potential to estimate blood pressure non-invasively, continuously and without a cuff. Recent studies suggest that PTT is not only related to systolic blood pressure (SBP) but also to heart rate. Therefore, in this study, variability of PTT is analyzed together with the variabilities of R–R interval (RRI) from electrocardiogram and beat-to-beat SBP on 9 normotensive subjects before and shortly after three successive bouts of treadmill exercise. The results showed that both low frequency (LF) and high frequency (HF) components were found in the spectra of RRI, SBP and PTT in the 5-min recordings collected before and after exercise. Compared to the baseline, a decrease in the power of the HF component of RRI followed by an increase in its LF component indicated firstly a vagal withdrawal and then sympathetic activity enhancement after successive bouts of exercise. On the other hand, although changes in the LF and HF components of PTT were more similar to those of SBP than of RRI, the LF/HF ratio of SBP was almost 4 times higher than that of PTT. Based on the results, it is therefore suggested that the relationship between SBP and PTT is frequency-dependent.     

Variability of heart rhythm in dynamic study of the psychovegetative relationship in neurogenic syncope

Physiological changes accompanying syncopes of neural origin (SNO) in patients with psychovegetative syndrome are still insufficiently studied. The data concerning the role of the autonomic nervous system are discrepant. Heart rate variability was analyzed in 68 patients with SNO in a supine position and during the active 20-min orthostatic test taking into account the heart rate components of very low frequency (VLF, an index of cerebral sympathetic activity) and high frequency (HF, a marker of vagal modulation). Steady growth of the VLF and progressive decrease in the LF within 15-20 min of the orthostasis were observed in all the patients (n = 33), who fainted after this period. The predominance of the VLF in the heart rate power spectra was correlated with a high level of anxiety. It is suggested that this fact indicates the stable cerebral sympathetic activation resulting in a baroreceptor dysfunction, i.e., a failure of vasomotor regulation in patients with SNO.     

Power spectral analysis of heart rate variability for assessment of diurnal variation of autonomic nervous activity in guinea pigs.

We established characteristics of power spectral analysis of heart rate variability, and assessed the diurnal variations of autonomic nervous function in guinea pigs. For this purpose, an electrocardiogram (ECG) was recorded for 24 hr from conscious and unrestrained guinea pigs using a telemetry system. There were two major spectral components, at low frequency (LF) and high frequency (HF) bands, in the power spectrum of HR variability. On the basis of these data, we defined two frequency bands of interest: LF (0.07-0.7 Hz) and HF (0.7-3.0 Hz). The power of LF was higher than that of HF in the normal guinea pigs. Atropine significantly reduced power at HF. Propranolol also significantly reduced power at LF. Furthermore, the decrease in the parasympathetic mechanism produced by atropine was reflected in a slight increase in the LF/HF ratio. The LF/HF ratio appeared to follow the reductions of sympathetic activity produced by propranolol. Autonomic blockade studies indicated that the HF component reflected parasympathetic activity and the LF/HF ratio seemed to be a convenient index of autonomic balance. Nocturnal patterns, in which the values of heart rate in the dark phase (20:00-06:00) were higher than those in the light phase (06:00-20:00), were observed. However, the HF, LF and the LF/HF ratio showed no daily pattern. These results suggest that the autonomic nervous function in guinea pigs has no clear circadian rhythmicity. Therefore, this information may be useful for future studies concerning the autonomic nervous function in this species.     

迷走神经在心率变异性中的作用

采用功率谱和近似熵 (approximateentropy ,ApEn)的方法 ,分析清醒家兔在双侧迷走神经保留 ,右、左侧迷走神经切断以及双侧迷走神经同时切断时心搏间期 (RRI)的变化。结果显示 :双侧迷走神经保留时功率谱中高频功率 (HF)、低频功率 (LF)及ApEn值均高于双侧及单侧迷走神经切断时 (P <0 0 5 ) ,LF/HF比值最小 ;切断单侧迷走神经 ,ApEn变小 ,LF/HF比值在右侧迷走神经切断时增大 ,而切断左侧迷走时LF/HF比值无明显变化 ;双侧迷走神经切断后LF/HF比值最大 ,ApEn最低。结果表明 :心率变异主要由迷走神经调节 ,右侧迷走神经起主要作用 ;传统心率变异性测量方法与非线性方法所得结果一致     

Capsaicin increases modulation of sympathetic nerve activity in rats: measurement using power spectral analysis of heart rate fluctuations

We assessed the sympatho-vagal activities of the heart after administration of capsaicin by measuring the power spectral analysis in rats. There were major two frequency components of heart rate variability, which we defined as high (1.0 Hz <, HF) and low (LF, < 1.0 Hz) frequency components. Vagal blockade by atropine abolished the high frequency component, and lowered the amplitude of the low frequency component. On the other hand, under conditions of sympathetic blockade by propranolol, the low frequency component was reduced. Combined vagal and sympathetic blockade abolished all heart rate fluctuations. We analyzed the low and high frequency components by integrating the spectrum for the respective band width. The rats administered capsaicin had a higher heart rate and sympathetic nervous system index (LF/HF) than the control group of rats. These results suggest that power spectral analysis is an effective and noninvasive method for detecting subtle changes in autonomic activity in response to the intake of foods or drugs.     

Effects of psychological stress on autonomic control of heart in rats.

The aim of this study was to examine the effects of psychological stress on autonomic control of the heart in rats. For this purpose, we evoked anxiety-like or fear-like states in rats by means of classical conditioning and examined changes in autonomic nervous activity using an implanted telemetry system and power spectral analysis of heart rate variability. Anxiety-like states resulted in a significant increase in heart rate (HR), low frequency (LF) power, and LF/HF ratio, with no change in high frequency (HF) power. Fear-like states resulted in a significant increase in HR and a significant decrease in HF power with no significant change in both LF power and LF/HF ratio, although LF/HF ratio increased slightly. These results suggest that autonomic balance becomes predominant in sympathetic nervous activity in both anxiety-like and fear-like states. These changes in rats correspond to changes which are relevant to cardiovascular diseases in humans under many kinds of psychological stress. Therefore, the experimental design of this study is a useful experimental model for investigating the effects of psychological stress on autonomic control of the heart in humans.