迷走神经切断后大鼠心房室结区神经肽变化的研究

切断大鼠颈部一侧迷走神经后，用组织化学方法结合图像分析定量观察了心房室结区乙酰胆碱酯酶，神经肽Ｙ（ＮＰＹ）、血管活性肠肽（ＶＩＰ）和降钙素基因相关肽（ＣＧＲＰ）的变化，同时用生物深化法测定了ＡＶＮ区ＡＣＨＥ、去甲肾上腺素（ＮＡ）的含量。并用逐步回归分析了各递质间的相互关第。本实验发现：ＡＶＮ区有ＮＰＹ、ＶＩＰ、ＣＧＲＰ免疫反应神经纤维和神经细胞。图像分析表明，左侧或右侧迷走神经切断５ｄ后ＡＶＮ区Ｎ     

不同年龄大鼠心窦房结和房室结毛细血管电镜定量观察

不同年龄大鼠心窦房结和房室结毛细血管电镜定量观察徐鹏霄李积胜贺智（天津武警医学院解剖教研室）为探讨老年人房性心律紊乱高发的原因，我们在总结国内外对人心传导系增龄变化研究（仍停留在光镜水平）的基础上，对大鼠心窦房结（ＳＡＮ）和房室结（ＡＶＮ）的增龄变化...     

大鼠视交叉上核内VIP,AVP及SOM样神经元的相互关系——免疫组化…

视交叉上核具有生物钟功能已为很多实验研究所证实，但其功能机制尚在探索之中，本实验采用双重免疫组织化学反应技术对大鼠视交叉上核内ＶＩＰ，ＡＶＰ及ＳＯＭ样三大神经元群之间的相互联系进行了观察。结果表明：（１）ＶＩＰ样扣结广泛分布于ＡＶＰ样神经元周围，数量最多，密度最大，而ＳＯＭ样扣结贴附于ＶＩＰ及ＡＶＰ样神经元的数量次之；（２）ＡＶＰ样扣结与ＶＩＰ样神经元之间，ＶＩＰ样扣结与ＳＯＭ样神经元之间也形成联     

大鼠视交叉上核内VIP、AVP及SOM样神经元的相互关系──免疫组化双重反应法研究

视交叉上核具有生物钟功能已为很多实验研究所证实，但其功能机制尚在探索之中。本实验采用双重免疫组织化学反应技术对大鼠视交叉上核内ＶＩＰ、ＡＶＰ及ＳＯＭ样三大神经元群之间的相互联系进行了观察．结果表明：（１）ＶＩＰ样扣结广泛分布于ＡＶＰ样神经元周围，数量最多、密度最大；而ＳＯＭ样扣结贴附于ＶＩＰ及ＡＶＰ样神经元的数量次之；（２）ＡＶＰ样扣结与ＶＩＰ样神经元之间，ＶＩＰ样扣结与ＳＯＭ样神经元之间也形成联系．上述发现为视交叉上核功能机制的研究提供了进一步的形态学依据．     

心脏传导系统取材方法的改进

心脏传导系统取材方法的改进罗斌①宋一璇①ＰｈｉｌｉｐＳ．Ｌ．Ｂｅｈ②ＰａｕｌＤｉｃｋｅｎｓ②祝家镇①毕启明①心脏传导系统（ＧａｒｄｉａｃＣｏｎｄｕｃｔｉｎｇＳｙｓｔｅｍ，ＣＣＳ）是由窦房结（ＳＡＮ）、房室结（ＡＶＮ）、房室束（ＨＢ）、左右束支（ＬＢＢ...     

人心传导系统纵切取材法及组织学观察

为研究心脏传导系统（ＣＣＳ）增龄性变化、病理改变及其与猝死的关系，在前人基础上建立了一种简便的ＣＣＳ取材方法。采用与窦房结（ＳＡＮ）、房室结（ＡＶＮ）长轴平行的纵切取材法，切取１４４例１０％福尔马林液固定、不同年龄非心性疾病死亡者心脏标本。该法具有如下特点；（１）ＣＣＳ定位标志清楚，故能准确取材；（２）ＳＡＮ、ＡＶＮ纵轴比横轴长２－３倍，故沿纵轴切片的数量远比横切法少；（３）可在一张切片上观察到更     

多重引物聚合酶链反应扩增丙型肝炎病毒基因及基 …

利用聚合酶链反应（ＰＣＲ）技术对丙型肝炎病毒（ＨＣＶ）的５’－非编码区（５’－ＮＣＲ）、Ｃ及ＮＳ４基因区的３对引物分别及同时扩增，检测８０例抗－ＨＣＶ阳性患者的血清ＨＣＶ ＲＮＡ，并进行了ＨＣＶ基因分型研究。各不同引物所介导的ＰＣＲ检出ＨＣＶ ＲＮＡ的结果为：５’－ＮＣＲ基因区６０％（４８／８０），Ｃ基因区３７％（３０／８０），ＮＳ４基因区３０％（２４／８０）。以上３对引物同时扩增仅４２％（３４／     

人胎儿胸腺精氨酸-加压素、血管活性肠肽和5-羟色胺免疫反应细胞

目的：通过观察神经肽及生物胺在胸腺中的分布，探讨胸腺神经内分泌的性质和神经肽及生物胺在胸腺中的生物学意义。方法：应用胎儿胸腺冰冻切片，采用ＰＡＰ免疫组织化学法，行ＡＶＰ、ＶＩＰ和５－ＨＴ免疫组织化学染色。结果：在胸腺的实质和小叶间隔中均可见到ＡＶＰ、ＶＩＰ和５－ＨＴ免疫反应细胞。ＡＶＰ免疫反应细胞主要分布于被膜下皮质内，ＶＩＰ和５－ＨＴ免疫反应细胞主要分布于被膜下皮质区和皮髓质交界区。５－ＨＴ免疫反应细胞的数量为最多。结论：胎儿胸腺中存在着弥散神经内分泌细胞。它们可以产生ＡＶＰ、ＶＩＰ和５－ＨＴ，通过内分泌和旁分泌等方式，调节胸腺的生理功能。     

HCV感染后NS5区抗体的动态观察与检测意义

本文报道用ＨＣＶＮＳ５区两段抗原性较好的合成肽研制的ＥＬＩＳＡ试剂盒及ＵＢＩＨＣＶＮＳ５区抗体检测ＥＬＩＳＡ试剂盒观察１４例ＨＣＶ感染者ＮＳ５区抗体的动态变化，证实ＮＳ５区抗体如同ＮＳ４区抗体一样比Ｃ及ＮＳ３区抗体出现晚。ＮＳ５区抗体总体检出率近似于ＮＳ４区抗体；１．５５％的血清为单独ＮＳ５区抗体阳性；存在ＮＳ５区抗体与其他区抗体滴度有互补作用的标本等提示ＮＳ５区抗体仍有一定的诊断价值。采用ＵＢＩＮＳ５区抗体检测试剂盒发现，９５．６５％（２２／２３）ＵＢＩ试剂盒诊断为ＮＳ５区抗体阳性的标本中含ＨＣＶＲＮＡ，６／１４ＨＣｖ感染者用ＵＢＩ试剂盒检出的抗体出现在ＡＬＴ再次异常升高或剧烈升高（高于参考值的３倍以上）前后，４／１４的感染者抗体出现于ＡＬＴ首次升高前后（其余４／１４的感染者未检出抗ＮＳ５抗体），因此ＵＢＩ抗ＨＣＶＮＳ５抗体诊断试剂盒检测的抗体似与疾病的活动有关。     

室房起搏对麻醉犬血液动力学参数及心血管活性物质浓度的影响

临床上常采用安置起搏器的方法治疗缓慢型心律失常，但少数病人在安置起搏器后，可出现血压下降，心输出量明显减少及头晕、疲乏等症状称之为起搏器综合征。其主要原因可能与ＶＶＩ方式起搏时，室房（Ｖ－Ａ）逆传，房室兴奋收缩协同性紊乱导致的血液动力学紊乱有关；研究亦发现，ＶＶＩ方式起搏，可使心房利钠因子（ａｔｒｉａｌｎａｔｒｉｕｒｅｔｉｃｆａｃｔｏｒ，ＡＮＦ）和血管紧张素ＩＩ（ａｎｇｉｏｔｅｎｓｉｎＩＩ，ＡｎｇⅡ）血浓度升高。本研究采用室房起搏模拟室房传导，初步探讨了其对血液动力学参数及ＡＮＦ，ＡｎｇⅡ和内源…     

Disruption of RHOA-ROCK Signaling Results in Atrioventricular Block and Disturbed Development of the Putative Atrioventricular Node

The RHOA-ROCK signaling pathway is involved in numerous developmental processes, including cell proliferation, differentiation and migration. RHOA is expressed in the atrioventricular node (AVN) and altered expression of RHOA results in atrioventricular (AV) conduction disorders in mice. The current study aims to detect functional AVN disorders after disturbing RHOA-ROCK signaling in chicken embryos. RHOA-ROCK signaling was inhibited chemically by using the Rho-kinase inhibitor compound Y-27632 in avian embryos (20 experimental and 29 control embryos). Morphological examination of control embryos show a myocardial sinus venosus to atrioventricular canal continuity, contributing to the transitional zone of the AVN. ROCK inhibited embryos revealed lateralization and diminished myocardial sinus venosus to atrioventricular canal continuity and at the severe end of the phenotype hypoplasia of the AVN region. Ex ovo micro-electrode recordings showed an AV conduction delay in all treated embryos as well as cases with first, second (Wenkebach and Mobitz type) and third-degree AV block which could be explained by the spectrum of severity of the morphological phenotype. Laser capture microdissection and subsequent qPCR of tissue collected from this region revealed disturbed expression of HCN1, ISL1, and SHOX2. We conclude that RHOA-ROCK signaling is essential for normal morphological development of the myocardial continuity between the sinus venosus and AVN, contributing to the transitional zone, and possibly the compact AVN region. Disturbing the RHOA-ROCK signaling pathway results in AV conduction disturbances including AV block. The RHOA-ROCK inhibition model can be used to further study the pathophysiology and therapeutic strategies for AV block. Anat Rec, 302:83–92, 2019. © 2018 Wiley Periodicals, Inc.     

家兔房室交界区及其心房传导通路的形态学研究

目的：探讨射频消融改良房室交界区的形态学基础。方法：健康成年家兔10只，分别做房室交界区的额状面、矢状面及水平面连续切片，在HE、Masson及磷钨酸苏木素染色下观察其形态学特征。结果：家兔房室结位于房室隔内中心纤维体的右侧，主要由P细胞和T细胞组成，以P细胞为主，其向后形成的延伸部同射频消融慢径的部位吻合，且细胞分布明显较房室结稀疏，内有胶原纤维分隔。同时有四条过渡细胞带分别从心房的不同部位到达房室结及后延伸部，分别称为左房结束、右房结束、后房结束及上房结束。另外，在冠状窦前壁有P细胞成团分布。结论：①房室交界区的概念应当扩大，分布范围从房室隔内中心纤维体的右侧一直向后接近冠状窦口，前部可能为快传导区，后部可能为慢传导区。②房内传导通路确有存在，并且可能参与了房内折返性心律失常的形成。③冠状窦是一个重要的结外潜在起搏点，可能与某些房性自律性心律失常的发生有关。     

人心传导系统的变异

目的　探讨划分心传导系统 (CCS)形态变异与发育异常 (畸形 )的界线。　方法　用我们建立的CCS检查法 ,即窦房结和房室结沿其长轴切 1～ 2块 ,房室束沿长轴垂直切 2～ 4块 ,连续切片 ,间断取片 ,每例共取 30片。对 886例 (非心源性死亡 737例 ,心源性猝死 149例 )人CCS进行组织学观察 ,并对两组进行CCS形态、死因分析比较。　结果　 1 人CCS具有大小、位置及形态的先天性变异 ;2 也有增龄性变化的后天性变异 ;3 死因不明的心源性猝死者中CCS见到有成年人胎儿型房室结、房室结全部移位至房室束穿部、房室束穿部完全分成 3束以上、房室束分叉部房室结化及移位至三尖瓣根部等 ,这些改变不应认为是正常变异 ,因为它们都可能有病理学意义。　结论　房室束分叉部向室间隔膜部内移位、偏位于室间隔左侧、向室间隔左下侧移位 ,以及不足 1 2房室结移位至中心纤维体内 (房室束穿部 ) ,心肌束移位于房室束或左束支内等应属CCS变异 ,不是畸形。     

Structure-function relationship in the AV junction

In the normal heart, the atrioventricular node (AVN) is part of the sole pathway between the atria and ventricles. Under normal physiological conditions, the AVN controls appropriate frequency-dependent delay of contractions. The AVN also plays an important role in pathology: it protects ventricles during atrial tachyarrhythmia, and during sinoatrial node failure an AV junctional pacemaker can drive the heart. Finally, the AV junction provides an anatomical substrate for reentry. Using fluorescent imaging with voltage-sensitive dyes and immunohistochemistry, we have investigated the structure-function relationship of the AV junction during normal conduction, reentry, and junctional rhythm. We identified molecular and structural heterogeneity that provides a substrate for the dual-pathway AVN conduction. We observed heterogeneity of expression of three isoforms of connexins: Cx43, Cx45, and Cx40. We identified the site of origin of junctional rhythm at the posterior extension of the AV node in 79% (n = 14) of the studied hearts. This structure was similar to the compact AV node as determined by morphologic and molecular investigations. In particular, both the posterior extension and the compact node express the pacemaking channel HCN4 (responsible for the I(F) current) and neurofilament 160. In the rabbit heart, AV junction conduction, reentrant arrhythmia, and spontaneous rhythm are governed by heterogeneity of expression of several isoforms of gap junctions and ion channels. Uniform neurofilament expression suggests that AV nodal posterior extensions are an integral part of the cardiac pacemaking and conduction system. On the other hand, differential expression of Cx isoforms in this region provides an explanation of longitudinal dissociation, dual-pathway electrophysiology, and AV nodal reentrant arrhythmogenesis.     

Inhibition of sarcoplasmic reticulum Ca2+-ATPase decreases atrioventricular node-paced heart rate in rabbits

Recent data indicate that Ca(2+) cycling in isolated atrioventricular node (AVN) cells contributes to setting spontaneous rate. The aim of the present study was to extend this observation to the intact AVN in situ, by evaluating the effects of inhibiting sarcoplasmic reticulum Ca(2+) uptake with cyclopiazonic acid (CPA) on intact AVN spontaneous activity and its response to isoprenaline. A model of the AVN-paced heart was produced to investigate intact AVN automaticity, by surgical ablation of the sino-atrial node (SAN) in the rabbit Langendorff-perfused heart. Electrograms were recorded from a site close to the AVN (triangle of Koch), an atrial site above the AVN, the left atrium and right ventricle, enabling AVN pacing of the preparation to be confirmed. Before SAN ablation, the heart rate was 166.8?±?5.4?beats min(-1). Ablation of the SAN was clearly indicated by a sudden and significant decrease of heart rate to 108.6?±?9.6?beats min(-1) (P?相似文献   

Characteristics of single cells isolated from the atrioventricular node of the adult guinea-pig heart

To date, data regarding the cellular electrophysiology of the atrioventricular node (AVN) have derived from AVN cells isolated from the rabbit heart. The aim of this study was to characterise for the first time the electrophysiological properties of single cells isolated from the AVN of the guinea-pig heart. Cells were isolated from the AVN region by a combination of enzymatic and mechanical dispersion. Mean (+/-SEM) cell dimensions were 110.8+/-2.3 microm in length by 11.4+/-1.3 micro m in width (n=76 cells). Electrophysiological recordings were made using the whole-cell patch-clamp technique at 37 degrees C. Mean cell capacitance was 25.1+/-0.9 pF (n=43) and mean cell input resistance was 1,377+/-178 Muomega (n=21). Spontaneously active cells exhibited action potentials characteristic of cardiac pacemaker tissue. Under whole-cell voltage clamp, the mean 'zero current' potential was -39.7+/-4.1 mV (n=21). Voltage commands of 500 ms duration to a range of test potentials from a holding potential of -40 mV revealed a number of distinct current components. At potentials positive to -40 mV an early inward current was observed that exhibited a bell-shaped current voltage (I-V) relation, typical of L-type calcium current. A delayed outward current that increased progressively with test potential magnitude was also observed. Analysis of the outward current 'tails' on repolarisation to -40 mV showed this to be comprised of two components with half-maximal activation voltages of -17.2+/-1.8 mV, and +27.1+/-3.6 mV (n=13). 'Transient outward' current appeared absent from guinea-pig AVN cells. Hyperpolarising test pulses activated net inward current, for which three components could be observed: a barium-sensitive (100 microM Ba(2+)) inwardly rectifying current evident at the start of the voltage command and prominent at potentials negative to the diastolic potential range; a time-dependent, hyperpolarisation-activated current, and a residual background current. On repolarisation to -40 mV, a large inward current spike typical of cardiac Na current was observed in some cells. Notably, the following electrophysiological characteristics of guinea-pig AVN cells are distinct from those characteristics previously reported for the rabbit AVN: (1) an absence of transient outward current, (2) the presence of two components of delayed outward current, and (3) the presence of a Ba(2+)-sensitive inwardly rectifying current at negative voltages. The guinea-pig AVN isolated cell preparation may be valuable in providing additional insights into the cellular electrophysiology of this important region of the heart.     

婴幼儿和法洛氏四联症房室结和房室束的外科解剖及计算机三维重建Ⅰ.位置与毗邻

通过对15例人心(成人5例,婴幼儿5例,法四5例)房室结和房室束的连续切片观察和图像分析,表明:15例房室结均位于Koch三角内.与成人相比,婴幼儿房室结位置相对较高,法四房室结位置偏低,其结前部紧靠三尖瓣隔瓣根部.婴幼儿房室束多位子三尖瓣隔瓣附着缘以上的房室肌隔内或室嵴顶部,而法四房室束起始部紧邻三尖瓣隔瓣根部的深面,其余部份可位:室嵴左侧,室缺的后下缘;房室束可直接位于室缺游离缘的心内膜下,或距室缺游离缘(可为肌性或腱性)1.88-2.14mm处.为临床小儿心外科手术提供了直接的形态学依据.     

力竭性游泳对大鼠房室结糖原和酶组织化学的影响

目的:探讨力竭性游泳对大鼠房室结(AVN)糖原和酶组织化学的影响。方法:建立大鼠力竭性游泳模型,运用组织化学技术,结合数字图像分析方法,观测房室结糖原(Gly)含量和乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、单胺氧化酶(MAO)和乙酰胆碱脂酶(ACHE)分布与含量的变化。结果:与对照组相比,1次力竭性游泳后房室结的Gly含量下降,LDH活性增强,SDH、MAO和ACHE的活性均减弱;与1次力竭组相比,1周力竭后Gly含量上升,LDH、SDH和MAO活性均减弱,ACHE活性增强。结论:力竭性游泳对房室结的糖原和酶组织化学的影响较为明显,这可能是造成房室结功能改变的因素之一。     

Specific pattern of ionic channel gene expression associated with pacemaker activity in the mouse heart

Even though sequencing of the mammalian genome has led to the discovery of a large number of ionic channel genes, identification of the molecular determinants of cellular electrical properties in different regions of the heart has been rarely obtained. We developed a high-throughput approach capable of simultaneously assessing the expression pattern of ionic channel repertoires from different regions of the mouse heart. By using large-scale real-time RT-PCR, we have profiled 71 channels and related genes in the sinoatrial node (SAN), atrioventricular node (AVN), the atria (A) and ventricles (V). Hearts from 30 adult male C57BL/6 mice were microdissected and RNA was isolated from six pools of five mice each. TaqMan data were analysed using the threshold cycle ( C _t) relative quantification method. Cross-contamination of each region was checked with expression of the atrial and ventricular myosin light chains. Two-way hierarchical clustering analysis of the 71 genes successfully classified the six pools from the four distinct regions. In comparison with the A, the SAN and AVN were characterized by higher expression of Navβ1, Navβ3, Cav1.3, Cav3.1 and Cavα2δ2, and lower expression of Kv4.2, Cx40, Cx43 and Kir3.1. In addition, the SAN was characterized by higher expression of HCN1 and HCN4, and lower expression of RYR2, Kir6.2, Cavβ2 and Cavγ4. The AVN was characterized by higher expression of Nav1.1, Nav1.7, Kv1.6, Kvβ1, MinK and Cavγ7. Other gene expression profiles discriminate between the ventricular and the atrial myocardium. The present study provides the first genome-scale regional ionic channel expression profile in the mouse heart.