清醒高血压大鼠心率变异分析的动物模型建立

目的：研究两种不同血浆肾素水平高血压大鼠心率变异的变化,进而探讨肾素。血管紧张素系统（RAS）影响心率变异（HRV）的机制。方法：制备两种高血压大鼠模型,采集其连续心电图数据。分析HRV的变化。并测定血浆血管紧张素Ⅱ（AngⅡ）的浓度。结果：肾性高血压大鼠血浆AngⅡ明显升高（P〈0．01）,心率变异频域指标中TP（总功率谱）、VLF（极低频功率）、LF（低频功率）和HF（高频功率）明显降低,LF／HF（低高频比）升高;DOCA-盐型高血压大鼠血浆AngⅡ水平明显降低,TP、VLF、LF和HF也明显降低。LF／HF比值升高。结论：两种不同血浆肾素水平的高血压大鼠交感和迷走神经均受损,同时交感神经活性相对占优势;提示肾素血管紧张素系统是通过脑内RAS的激活而影响HRV,不是循环RAS的外周作用。     

缬沙坦对气道平滑肌增殖的影响及机制探讨

目的:观察血管紧张素ⅡⅠ型受体拮抗剂对气道平滑肌细胞增殖的影响.方法:体外培养人体气道平滑肌细胞(HASMCs),用血管紧张素Ⅱ(AngⅡ)和AngⅡ的Ⅰ型受体拮抗剂缬沙坦予以干预,四甲基偶氮唑蓝(MTT)微量比色法测定HASMCs生长率,流式细胞术检测HASMCs细胞周期,实时荧光定量PCR(Real time PCR)检测HASMCs转化生长因子β1(TGF-β1)mRNA的变化.结果:(1)AngⅡ刺激HASMCs后细胞生长率明显高于对照组(P＜0.05),AngⅡ+缬沙坦组细胞生长率明显低于AngⅡ组(P＜0.05);(2)AngⅡ刺激HASMCs后细胞周期S期比例显著高于对照组(P＜0.05),AngⅡ+缬沙坦组细胞周期S期比例低于AngⅡ组(P＜0.05);(3)AngⅡ刺激HASMCs后TGF-β1 mRNA表达量明显高于对照组(P＜0.05),AngⅡ+缬沙坦组TGF-β1mRNA表达量低于AngⅡ组(P＜0.05).结论:血管紧张素ⅡⅠ型受体拮抗剂能抑制气道平滑肌的增殖,可能通过下调TGF-β1起作用.     

血管紧张素Ⅱ对废用性骨骼肌萎缩肌纤维类型的影响

目的:观察血管紧张素Ⅱ在废用性肌萎缩过程中对骨骼肌肌纤维类型转化的影响。方法:以雌性SD大鼠为研究对象,按随机配对原则分成4组(n=8):即假手术组(C)、AngⅡ组(CA)、悬吊组(T)和悬吊+AngⅡ(TA)。ATPase染色法分析评价各组肌纤维类型的转化情况。结果:T组与C组相比,Ⅱ型肌纤维比例显著升高(P<0.05),而TA组与T组相比Ⅱ型肌纤维比例下降(P<0.05)。结论:在骨骼肌萎缩过程中,肌纤维类型出现Ⅰ型肌纤维向Ⅱ型肌纤维类型的转化;而血管紧张素Ⅱ在骨骼肌萎缩过程中抑制了肌纤维类型由慢向快的转化。     

扩张型心肌病患者恶性室性心律失常与心率变异性关系分析

目的:了解扩张型心肌病患者恶性心律失常(MVA)与心率变异性(heart rate variability,HRV)的关系,探讨扩心病患者体内自主神经变化的临床意义。方法:选择扩心病患者48例作为研究对象,同时按照年龄配对,取48例正常者作为对照组,对其行24小时动态心电图检查,依据其是否出现恶性心律失常分为恶性室性心律失常(MVA+)组及单纯扩张型心肌病(MVA-)组,分析组间HRV的差异。结果:与对照组比较,单纯扩张型心肌病(MVA-)组HRV时域指标(SDNN、SDANN、RMSSD)均有降低(P<0.05)L与(MVA-)组相比,恶性室性心律失常(MVA+)组HRV相关指标进一步降低(P<0.05)。结论:自主神经功能异常是扩张型心肌病患者恶性心律失常的重要危险因子,可能可以用HRV预测其发生恶性心律失常危险性。     

肾上腺髓质素2的降压作用及其机制

目的:研究肾上腺髓质素2(ADM2)拮抗血管紧张素Ⅱ(AngⅡ)发挥舒张血管的作用及机制。方法:将18只180~200 g雄性SD大鼠随机分为3组(n=6):对照组、AngⅡ(150 ng/(kg·min))组和AngⅡ(150 ng/(kg·min))+ADM2(500 ng/(kg·h))组,采用皮下埋植微量渗透泵的方法给药。2周后颈动脉插管法测量大鼠血压,测定血浆一氧化氮(NO)含量和内皮型一氧化氮合酶(eNOS)活性。DHE染色法检测大鼠动脉壁活性氧产生。制备大鼠离体血管环,观察ADM2的舒血管作用。培养人脐静脉内皮细胞系EA.hy 926,用DCFH-DA荧光探针检测AngⅡ和ADM2对血管内皮细胞活性氧释放的影响。结果:与AngⅡ组相比,ADM2显著降低了大鼠血压,血浆中eNOS活性提高、NO含量增加,血管壁活性氧产生减少。ADM2呈浓度依赖性和内皮依赖性舒张血管环,并明显抑制了AngⅡ引起的血管内皮细胞活性氧产生。结论:ADM2可能通过拮抗AngⅡ诱导的血管内皮氧化应激效应,改善内皮功能,发挥舒张血管、降低血压的作用。     

肾素- 血管紧张素- 醛固酮系统与原发性高血压病的关系

目的:探讨血浆肾素-血管紧张素系统与原发性高血压病的关系。方法:采用病例-对照研究设计,入选125例原发性高血压病患者与60例血压正常健康体检者为对照组。采用放射免疫方法测定立位、卧位血浆肾素活性(PRA),醛固酮(ALD)浓度及血管紧张素Ⅱ(AngⅡ)浓度。结果:原发性高血压患者,立位、卧位血浆PRA均低于正常对照组(P<0.05),而ALD浓度及AngⅡ浓度均高于正常对照组(P<0.05)。根据高血压病1级、2级、3级分组,立位、卧位血浆PRA均依次降低(P<0.05);而ALD浓度及AngⅡ浓度依次升高(P<0.05)。结论:肾素-血管紧张素-醛固酮系统与原发性高血压病的发病关系密切,血浆PRA水平、AngⅡ及ALD浓度有望成为原发性高血压病分级的有效指标;降低原发性高血压患者AngⅡ及ALD量是治疗高血压病的关键,血浆AngII、ALD也有望成为评价原发性高血压病疗效的指标。     

外源性Apelin-13 对心力衰竭大鼠血浆血管紧张素Ⅱ 和肾上腺髓质素的影响

目的:研究给予外源性Apelin-13治疗对血流动力学、血浆血管紧张素Ⅱ(Angiotensin-Ⅱ,AngⅡ)和肾上腺髓质素(Adrenomedulin,ADM)水平的影响。方法:将50只大鼠随机分为3组:心衰组(n=20)、治疗组(n=20)和正常对照组(n=10),阿霉素(ADR)腹腔注射建立大鼠心衰模型,治疗组给药外源性Apelin-13治疗,检测大鼠血浆AngⅡ和ADM水平(ELISA法)以及血流动力学的水平。结果:心衰组和治疗组血浆AngⅡ和ADM水平比正常对照组增高,但治疗组血浆AngⅡ和ADM水平比心衰组明显降低,治疗组左心室内压最大升降速度(LV±dp/dtmax)、左室最大收缩压(LVESP)比心衰组增高,左室舒张末期压(LVEDP)比心衰组低(P均<0.05)。结论:外源性apelin-13抑制体内的AngⅡ和ADM水平可能对ADR诱导的大鼠心衰有保护作用。     

非诺贝特通过FoxO1 抑制心肌肥大

目的:探讨非诺贝特(fenofibrate)对血管紧张素Ⅱ(AngⅡ)诱导的肥大心肌细胞的抑制作用及对FoxO1表达的影响。方法:首先采用AngⅡ诱导心肌细胞肥大,将细胞分为三组:对照组:未给予任何干预;心肌细胞肥大组:AngⅡ(10-7mol/L)刺激细胞;治疗组:先给予fenofibrate(10-5mol/L),30min后AngⅡ(10-7mol/L)刺激细胞。应用蛋白免疫印迹法(western-blotting)和实时定量PCR法(real time PCR)检测各组细胞中转录因子FoxO1的蛋白质及mRNA含量,心肌细胞肥大的判断使用脑钠肽(brain natriuret icpepide BNP)。结果:心肌细胞肥大组的FoxO1表达较对照组明显降低,而治疗组的FoxO1表达较心肌肥大组明显升高。结论:非诺贝特可能通过上调FoxO1表达,从而抑制心肌细胞肥大。     

学龄前儿童不同距离往返跑后HR和HRV改变的比较*

目的: 筛选一种适用于评估学前儿童速度和心功能的测试方法。方法: 选取某幼儿园30名健康儿童作为实验对象,分别建立“10 m、20 m和30 m往返跑”的运动模型,通过佩戴人体能耗检测仪的方式,监测其运动前后心率和心率变异性(HRV)指标的变化特征,进而通过计算其运动负荷和生理负荷指数,通过HRV时域、频域和庞莱恩散点图参数的变化,判断学前儿童在不同距离往返跑后心脏交感神经和迷走神经的活性与支配功能状态。结果: 儿童10 m、20 m和30 m往返跑依次为中、大和超大强度的范围;HRV指标测试结果显示:与运动前基线值相比较,三种往返跑后的R-R间期标准差(SDNN)均呈现显著性的降低;儿童30 m往返跑后,除了低频与高频的比值(LF/HF)显著升高(P<0.01),其余频域指标以及庞莱恩散点图参数较基线值均有不同程度的降低(P<0.05,0.01);此外,与10 m往返跑后相比较,儿童20 m往返跑后LF呈现显著性的增加(P<0.01),其余HRV指标均无显著性变化,但30 m往返跑后的HRV频域指标和庞莱恩散点图参数均不同程度呈现显著降低(P<0.05,0.01),且LF/HF值超出正常参考值范围。结论: 20 m往返跑后儿童的心交感神经活性和迷走神经活性变化不显著、综合调节能力未下降,心功能安全性较好。     

血管紧张素Ⅱ上调自发性高血压大鼠和Wistar-Kyoto大鼠血管平滑肌细胞外信号调节激酶的信号转导

本文研究血管紧张素Ⅱ(angiotensin Ⅱ,Ang Ⅱ)对自发性高血压大鼠(spontaneously hypertensive rat,SHR)和Wistar- Kyoto(WKY)大鼠血管平滑肌细胞(vascular smooth muscle cells．VSMCs)细胞外信号调节激酶(extracellular signal-regulated pro- tein kinases,ERKs)信号途径的影响。体外培养SHR和WKY大鼠的VSMCs,先在培养基中加入终浓度为1×105mmol／L 的缬沙坦或1×105mmol／L的PD98059或不加药物,再给予1×107mmol／L的Ang Ⅱ刺激24 h后收集细胞,以无血清培养基 培养的VSMCs作对照。用免疫沉淀法测定ERK活性;用Western-blot方法检测总ERK(total ERK,t-ERK)、磷酸化ERK (phosphorylated-ERK,p-ERK)及丝裂素活化蛋白激酶磷酸酶-1(mitogen-activated protem kinases phosphatase-1,MKP-1)水 平;用RT-PCR法半定量测定MKP-1 mRNA的含量。结果显示:(1)SHR和WKY大鼠Ang Ⅱ刺激组VSMCs中ERK活 性、p-ERK、MKP-1及MKP-1 mRNA水平均明显高于对照组(P<0．05);SHR和WKY大鼠Ang Ⅱ+缬沙坦组和Ang Ⅱ +PD98059组的上述指标与对照组比较均无显著性差异。(2)SHR大鼠VSMCs中ERK活性、P-ERK、MKP-1及MKP-1 mRNA均显著高于相同干预的WKY大鼠(P<0．01)。(3)SHR和WKY大鼠之间以及对照组、Ang Ⅱ刺激组、Ang Ⅱ+缬沙 坦组和Ang Ⅱ+PD98059组间VSMCs中t-ERK水平均无显著性差异。以上结果表明,Ang Ⅱ可能主要通过其1型(Ang Ⅱ type 1,AT)受体激活SHR和WKY大鼠VSMCs中ERK途径,增加ERK活性和p-ERK蛋白水平,继而引起MKP-1及 MKP-1 mRNA水平升高。     

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.     

Somatostatin and GABA correlate with cervical autonomic nerve activity

The mode of inhibitory action of centrally administered SRIF on the efferent activity of autonomic nerves was investigated in the rat by assessing the SRIF-induced change in the activity of the superior laryngeal nerve with or without pretreatment with various drugs. After picrotoxin or bicuculline treatment, the inhibition of nerve activity by SRIF was abolished while reserpine and atropine failed to abolish the SRIF effect. The centrally administered GABA inhibited the activity of the superior laryngeal nerve and the cervical sympathetic trunk. However, SRIF did not affect the sympathetic trunk. Arterial blood pressure was increased by SRIF while GABA produced hypotension.

These data provide evidence for a GABAergic system as the mediator of SRIF action in the brain and for the selectivity of SRIF action on the particular intermediary GABAergic neurones.     

高血压免疫机制的研究进展

高血压可引发多种心脑血管并发症,严重威胁人类健康。目前研究发现,高血压患者免疫调节功能异常,可导致持续性的炎症。而炎症可损伤血管内皮功能,激活肾素-血管紧张素系统,引起血管重构、血管硬化、血管舒缩功能异常等,加重高血压的发展。高血压患者免疫调节功能异常主要涉及非特异性免疫中的吞噬细胞对组织的浸润、树突细胞的抗原递呈、自然杀伤细胞的活化以及特异性免疫中T细胞的活化等。Toll样受体识别抗原启动免疫系统,从而引发炎症是高血压免疫机制的关键。自主神经系统也与高血压发生发展密切相关,自主神经对免疫具有调节作用,高血压患者自主神经失衡,导致免疫调节异常,引发心血管损伤,造成血管舒缩功能异常,从而加剧高血压的发展。因此,对神经免疫调节的研究有望为高血压的治疗提供新的策略。本文就高血压中免疫机制以及自主神经系统对免疫系统调节作用的研究进展作一综述。     

Novel Immunohistochemical Techniques Using Discrete Signal Amplification Systems for Human Cutaneous Peripheral Nerve Fiber Imaging

Confocal imaging uses immunohistochemical binding of specific antibodies to visualize tissues, but technical obstacles limit more widespread use of this technique in the imaging of peripheral nerve tissue. These obstacles include same-species antibody cross-reactivity and weak fluorescent signals of individual and co-localized antigens. The aims of this study were to develop new immunohistochemical techniques for imaging of peripheral nerve fibers. Three-millimeter punch skin biopsies of healthy individuals were fixed, frozen, and cut into 50-µm sections. Tissues were stained with a variety of antibody combinations with two signal amplification systems, streptavidin-biotin-fluorochrome (sABC) and tyramide-horseradish peroxidase-fluorochrome (TSA), used simultaneously to augment immunohistochemical signals. The combination of the TSA and sABC amplification systems provided the first successful co-localization of sympathetic adrenergic and sympathetic cholinergic nerve fibers in cutaneous human sweat glands and vasomotor and pilomotor systems. Primary antibodies from the same species were amplified individually without cross-reactivity or elevated background interference. The confocal fluorescent signal-to-noise ratio increased, and image clarity improved. These modifications to signal amplification systems have the potential for widespread use in the study of human neural tissues.     

宫颈癌患者行根治性子宫切除术且保留盆腔自主神经的效果观察

目的:探讨宫颈癌患者行保留盆腔自主神经的根治性子宫切除术的临床效果。方法:按照随机数字表法将入选的48例宫颈癌患者随机分为对照组和试验组两组,每组患者各24例,其中对照组患者均采用传统的宫颈癌根治手术治疗,而试验组患者则采用保留盆腔自主神经的根治性子宫切除术进行治疗,比较两组患者的术中情况和术后恢复情况等。结果:两组患者的子宫切除出血量和术中总出血量以及术中输血率均无明显差异(均P0.05),但是试验组患者的子宫切除时间和手术总时间显著长于对照组患者(t=2.934,P0.05;t=3.121,P0.05)。两组患者之间的术后排气、排便时间均无明显差异(均P0.05),提示两组患者术后直肠功能无明显差异;对照组患者的术后残余尿量100ml时间与术后残余尿量50ml时间均显著高于试验组患者(t=2.891,P0.05;t=3.092,P0.05)。术后试验组患者的首次排尿感和急迫排尿感以及最大腹压等均显著低于对照组患者(t=4.283,P0.05;t=4.027,P0.05;t=3.137,P0.05);而最大膀胱压和最大尿流量以及最大逼尿肌压等则显著高于对照组(t=3.192,P0.05;t=2.938,P0.05;t=3.572,P0.05)。结论:采取保留盆腔自主神经的根治性子宫切除术能够较好地减少宫颈癌患者临床并发症的出现,具有较好的治疗效果,值得加以推广和运用。     

激活蓝斑在孤束核水平对迷走神经传入的抑制

在戊巴比妥钠麻醉兔,电刺激颈迷走神经中枢端,在同侧孤束核（NTS）区可记录到一个由三个子波组成的复合电位。它们的潜伏期分别为6．8±0．6ms（P1）,25．8±4．2ms（P2）和89．1±2．7ms（P3）。这可能代表着不同性质的迷走传入纤维的突触后电位。同侧蓝斑（LC）内微量注射谷氨酸钠使P2,P3波的幅值明显降低。电刺激LC在同侧NTS区诱发出111个有反应单位,其潜伏期平均为6．3±1．4ms。在169个对迷走传入刺激有反应的NTS单位中,有90个对LC刺激也有反应。39个（占43．3％）会聚性单位对上述两种刺激的反应相似,而其余的呈不同的反应。对LC和迷走刺激分别均呈兴奋反应的25个NTS单位中,如预先刺激LC,则有14个单位对迷走刺激的兴奋反应受到明显抑制,另11个单位的兴奋反应完全被抑制。上述结果提示：激活蓝斑核具有抑制NTS对迷走传入刺激反应的作用。     

Manifestations of Peripheral Autonomic Insufficiency in Patients Suffering from Acute Inflammatory Demyelinating Neuropathies

We tried to characterize the frequency and significance of manifestations of peripheral autonomic insufficiency (PAI) in clinical cases of acute inflammatory demyelinating neuropathies (AIDN). Forty patients with the above diagnosis (21 men and 19 women, 16 to 72 years old) were examined. To detect symptoms attributable to PAI, we used Birkmayer–Vein tables; these data were compared with the results of electroneuromyographic (ENMG) examinations. In 38 and 2 cases, clinical manifestations of AIDN corresponded to the Guillain–Barre and Miller–Fisher syndromes, respectively. According to ENMG data, changes in the peripheral nerves and neuromuscular junctions corresponded to axonopathy, myelinopathy, and a mixed damage (myelinoaxonopathy) in 18 (45%), 14 (35%), and 8 (20%) patients, respectively. The following disturbances in the sphere of autonomic control were observed: orthostatic hypotension, in 28 cases (70%); tachycardia in the resting state, in 24 cases (60%); hypertension in the reclining position, in 16 cases (40%); hypohydrosis of the skin on the limbs, in 18 cases (45%); dyspepsia, in 8 cases (20%), and enuresis, in 3 cases (7.5%). Manifestations of PAI began to be observed in the earliest stage of the disease and were preserved within the period of recovery of the motor functions; they were more intensive in the cases of a severe clinical course of polyneuropathies. The severity of autonomic disorders strictly correlated with the level of axonal degeneration (characterized according to the ENMG data). The treatment used (i.v. injections of immunoglobulin, plasmapheresis, use of vasoactive and neurometabolic drugs) not only improved the state of the motor sphere but also decreased the intensity of PAI symptoms. Thus, in the cases of AIDN not only thick myelinated fibers of the peripheral nerves but also a significant proportion of thin fibers responsible for the control of automatic functions are subjected to damage. PAI is rather frequently observed in patients suffering from AIDN, and the level of its manifestation reflects the severity of the disease and intensity of damage to the peripheral nerves.     

The Effects of Leptin Administration in Non‐obese Human Subjects

Objective: Body fatness is partly under hypothalamic control with effector limbs that include the endocrine system and the autonomic nervous system (ANS). In previous studies of both obese and never‐obese subjects, we have shown that weight increase leads to increased sympathetic and decreased parasympathetic activity, whereas weight decrease leads to decreased sympathetic and increased parasympathetic activity. We now report on the effect of leptin, independent of weight change, on the ANS. Research Methods and Procedures: Normal weight males (ages 20–40 years) were fed a solid food diet, measured carefully to maintain body weight, for 3 weeks, as inpatients at the Rockefeller University General Clinical Research Center. In a single‐blind, 22‐day, placebo/drug/placebo design, six subjects received leptin 0.3 mg/kilogram subcutaneously for 6 days. ANS measures of amount of parasympathetic control and sympathetic control of heart period (interbeat interval) were made by sequential pharmacological blockade with intravenous atropine and esmolol. Norepinephrine, dopamine, and epinephrine levels in 24‐hour urine collections were also measured as well as resting metabolic rate. Results: Sufficient food intake maintained constant body weight in all subjects. There was no evidence that leptin administration led to changes in energy metabolism sufficient to require additional food intake or to alter resting metabolic rate. Likewise, leptin administration did not alter autonomic activity. Parasympathetic control and sympathetic control, as well as the urinary catecholamines, were not significantly affected by leptin administration. Glucose and insulin levels were increased by food intake as expected, but leptin had no affect on these levels before or after food intake. Discussion: ANS responses to changes in energy metabolism found when food intake and body weight are altered were not found in these never‐obese subjects given leptin for 6 days. Although exogenous leptin administration has profound effects on food intake and energy metabolism in animals genetically deprived of leptin, we found it to have no demonstrable effect on energy metabolism in never‐obese humans. The effects of longer periods of administration to obese individuals and to those who have lost weight demand additional investigation.     

Basal metabolic rate and autonomic nervous system dysfunction in men with spinal cord injury

Objectives: The purpose of this study was to determine the relationship between autonomic nervous system dysfunction and basal metabolic rate (BMR), and the effect of spasticity on basal metabolic rate. Research Method and Procedures: Twenty men (11 paraplegic and 9 tetraplegic) with American Spinal Injury Association (ASIA)‐A and ‐B grade chronic spinal cord injury (SCI) participated in this study. Total body fat mass and lean tissue mass were measured in all participants using DXA by standard methods. Patients were allocated into 2 groups to determine the effect of autonomic nervous system dysfunction on BMR: Group I (T6 and upper‐level injuries with history of autonomic dysreflexia) and Group II (T7 and lower‐level injuries without history of autonomic dysreflexia). Measurements of BMR were determined by indirect calorimetry under standardized conditions. Results: There were 13 patients in Group I and 7 patients in Group II and the difference between these two in terms of time since injury, BMI, age, weight, lean tissue mass, BMR, and BMR/kg were not significant. Conclusion: We concluded that autonomic nervous system dysfunction does not affect BMR, and it might be ignored in considering energy needs in spinal cord injury.