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1.
Fourier analysis was employed to determine the amplitudes of spectrum components of small variations of electrical resistance (bioimpedance) in human fi nger recorded using an original hardware-software complex. It revealed periodic bioimpedance oscillations at the frequencies of heartbeats, respiration, and Mayer wave (0.1 Hz). These periodic variations were observed under normal conditions and during circulation arrest in the arm. It is concluded that the spectrum peaks of bioimpedance variations in the phalanx of human finger reflect periodic blood pressure changes in the major vessels and rhythmic neural control of the regional vascular tone. During normal blood flow, the greatest amplitude of rhythmic changes in bioimpedance was observed at the heart rate; it surpassed by an order of magnitude the amplitudes of respiratory oscillations and Mayer wave. In contrast, the largest amplitude of rhythmical changes of the impedance during circulation arrest corresponded to the oscillations at respiration rate, while the amplitude of variations at the heart rate was the smallest. Under circulation arrest, the maximum frequency of bioimpedance variations was approximately 1.4 Hz (the third respiratory harmonic), which indicates the upper limit of frequency range of neural modulation of vascular tone in human finger. During normal respiration and circulation, two side cardiac peaks were revealed in bioimpedance amplitude spectrum, whose amplitude reflected the depth of the respiratory amplitude modulation of pumping action of the heart. During normal breathing, the second and the third harmonics of the cardiac bioimpedance variations were split reflecting respiratory frequency modulation of the heart rate.  相似文献   

2.
To evaluate the role of bladder afferent fibers in the hypogastric nerves (HGN) in modulation of the micturition reflex induced by chemical bladder irritation, voiding behavior, continuous cystometry, and spinal c-fos expression following intravesical acetic acid instillation were investigated in rats with or without HGN transection. Voiding behavior and continuous cystometry were examined in unanesthetized conscious rats. Following chemical bladder irritation, a significant increase in urinary frequency associated with a marked decrease in the voided volume per micturition, was noted in control rats with the intact HGN, but not in HGN-transected rats. Continuous infusion of acetic acid in control rats elicited irritative bladder responses characterized by a marked decrease in the intercontraction interval and a marked increase in maximal vesical pressure, both of which were absent in capsaicin-desensitized rats. HGN transection prevented the decrease in the intercontraction interval but not an increase in maximal vesical pressure following chemical bladder irritation. Compared with saline infusion, acetic acid infusion caused a significant increase in c-fos expression at L(1) and L(6) of the spinal cord, and HGN transection significantly reduced c-fos expression in the dorsal horn of the spinal cord at L(1) but not at L(6). These results suggest that capsaicin-sensitive bladder afferent fibers in the HGN, which travel through the rostral lumbar spinal cord, have a role in urinary frequency caused by chemical bladder irritation.  相似文献   

3.
Small variations of electric impedance (bioimpedance) of human penis were examined in healthy volunteers and in patients with vascular erectile dysfunction (ED). The harmonic analysis revealed rhythmic oscillations of penile bioimpedance at frequencies corresponding to the heart and respiration rates and Mayer wave (0.1 Hz) and to multiple frequencies (harmonics) of the respiratory and cardiac oscillations. In normal penile bioimpedance spectrum, the Mayer and respiratory peaks were several times higher than the first cardiac (pulsatile) harmonic indicating neurogenic origin of rhythmic bioimpedance variations in the whole penis. The most of healthy individuals (78%) demonstrated the cardiac harmonics at the frequency range of 4–7 Hz that violated the monotone decrement of the pulsatile harmonic series suggesting the resonant character of oscillations of the penile arteries at this “near” frequency range. In contrast to stable 1–4 cardiac harmonics, the amplitudes of the near-range resonant harmonics could vary during few minutes suggesting a causal relation of the corresponding bioimpedance oscillations with the varying vascular tone in penile arteries. The most patients (89%) with vascular ED demonstrated not only the first 1–4 monotonically decrementing harmonics and the near-resonant ones, but also the stable cardiac harmonics at the “far” frequency range of 8–14 Hz that also disturbed the monotonic character of the cardiac harmonic series indicating the sclerotic alterations in regional arteries. In ED patients, insignificant decrease of the initial cardiac harmonics C1-C3 in comparison with the norm was accompanied by pronounced and significant decrease of the respiratory R1 and Mayer M1 peaks. The study showed that the far-frequency bioimpedance resonances at the range of 8–14 Hz and dramatic drop of Mayer and respiratory peaks are the diagnostic signs of vascular ED independent on the accompanying hormonal or neurogenic disorders.  相似文献   

4.
We examined the effects of propiverine hydrochloride and naftopidil on the urinary ATP level and bladder activity after bladder stimulation in rats. Thirty-nine female rats were divided into a control group, a propiverine group, and a naftopidil group. Rats in the propiverine and naftopidil groups were administered 1 ml/day of propiverine or naftopidil dissolved in water at 5mg/ml, while animals in the control group were administered 1 ml of water only. After 2 weeks, 18 rats (6 per group) underwent continuous cystometry with physiological saline or 0.1% acetic acid solution and their bladder activity was recorded. In the remaining 21 rats (7 per group), 0.1% acetic acid solution was infused into the bladder and the urinary ATP level was measured before and after stimulation (days 0-7). During cystometry with acetic acid in the control group, the interval between bladder contractions was shorter and the maximum bladder contraction pressure was higher than the results for cystometry with physiological saline. The maximum bladder contraction pressure was also increased in the naftopidil group, but such a change was not seen in the propiverine group. The urinary ATP level increased significantly in all three groups after the infusion of acetic acid, but the increase of ATP was smaller in the propiverine group (45% of control) and the naftopidil group (62% of control) than in the control group on day 0. Therefore, the inhibitory effect of propiverine and naftopidil on bladder activity may be partly due to blocking ATP release from the bladder epithelium.  相似文献   

5.
To evaluate the role of protein kinase C in central muscarinic mechanisms regulating voiding, cystometry was performed in conscious rats. Oxotremorine methiodide, a muscarinic agonist was injected i.c.v. in a dose (0.1 microg/rat) shown previously to alter voiding function. Oxotremorine methiodide was also tested after i.c.v. injection of chelerythrine chloride (a protein kinase C inhibitor, 2 microg/rat) or 1-(5-isoquinolinesulfonyl)-2-methylpiperazine (H-7, a protein kinase inhibitor, 5 nmol/rat). In untreated rats, oxotremorine methiodide elicited a bimodal response consisting of an initial increase in bladder capacity, maximal voiding pressure, pressure threshold and post voiding intravesical pressure, but reduced voiding efficiency and bladder compliance. The second response consisted of a decrease in bladder capacity and bladder compliance, increases in maximal voiding pressure and post voiding intravesical pressure, but no change in pressure threshold or voiding efficiency. However, approximately 20 min after pre-treatment with chelerythrine chloride or H-7 in doses that did not alter voiding function, oxotremorine methiodide decreased bladder capacity, increased maximal voiding pressure, but did not change pressure threshold or voiding efficiency. These results indicate that inhibitory and facilitatory muscarinic mechanisms in the brain that control voiding function involve different second messenger systems. Inhibitory mechanisms which are blocked by chelerythrine chloride or H-7 must involve protein kinase C and normally be inactive because the protein kinase inhibitors alone did not alter voiding. On the other hand, facilitatory muscarinic mechanisms which previous studies showed were tonically active are not mediated by chelerythrine chloride or H-7 sensitive signaling pathways.  相似文献   

6.
Infravesical obstruction (IVO) secondary to benign prostatic hypertrophy can affect up to 50% of men over 50 years old and may cause serious and irreversible alterations throughout the urinary tract, especially in the bladder. Therapeutic approaches are currently limited. Amitriptyline has recently been described as an analgesic, anti-inflammatory and myorelaxant in some experimental models. The objective of this study was to investigate the effects of amitriptyline hydrochloride on the process of fibrosis in a bladder outlet obstruction model in rats. Male Wistar rats were subjected to IVO and studied at intervals of 1 and 14 days postprocedure. The rats were randomly divided into five groups: sham, IVO1-T, IVO1-NT, IVO14-T and IVO14-NT. Bladder tissue was processed for histopathology, immunohistochemistry and RT-PCR. The IVO14 groups presented bladder fibrosis, smooth muscle cell hypertrophy and bladder wall thickening. The IVO14-T group demonstrated a higher intensity of fibrosis, higher macrophage infiltration rate and higher gene expression of Transforming growth factor (TGF) Tgf-β1. Thus this data shows that in this experimental mode amitriptyline had an amplifying effect on the process of fibrosis as a whole.  相似文献   

7.
Objectives: Low intensity extracorporeal shock wave therapy (Li-ESWT) has proven to be effective and safe for the treatment of various urological disorders including erectile dysfunction and chronic pelvic pain syndrome. In this study, we elucidated the therapeutic effect and possible mechanisms of Li-ESWT on diabetic bladder dysfunction (DBD) in a rat model.Materials and Methods: In all, thirty-two female Sprague-Dawley rats were divided into three groups: normal control (NC), diabetes mellitus (DM) control, and DM Li-ESWT. The two DM groups were given high fat diets for one month, followed by 2 intraperitoneal injections of streptozotocin (STZ) 30 mg/kg separated by one week. Body weight and fasting blood glucose were monitored every week. Only rats with fasting blood glucose 140 mg/dL or more were considered diabetic and used in the subsequent portions of the study. The Li-ESWTs were applied toward the pelvis of the rats twice a week for 4 weeks with energy flux density (EFD) 0.02 mJ/mm2, 500 shocks, at 3Hz. All rats underwent plasma insulin tolerance test, conscious cystometry, leak-point pressure (LPP) assessment, and immunohistochemical studies.Results: DM groups had significantly lower insulin sensitivity and higher body weight. Conscious cystometry also revealed voiding dysfunctions. In the DM Li-ESWT group, the rats had significantly improved voiding functions that were reflected in longer micturition intervals and higher LPP compared to DM control. Immunofluorescence in DM control groups showed increased tyrosine hydroxylase (TH) expression and decreased neuronal nitric oxide synthase (nNOS) expression in the longitudinal urethral smooth muscles. Besides, rats had dilations and deformities of suburothelium capillary network of the bladder, revealing the deterioration of the nerve function of the urethra and destruction of the vascularization of the bladder. However, the DM Li-ESWT group exhibited recovery of the nerve expression of the urethra and vascularization of bladder.Conclusions: Li-ESWT ameliorates the bladder dysfunction and urinary continence in the DBD rat model, reflected in restoration of the nerve expression of the urethra and the vascularization of the bladder. Non-invasive Li-ESWT could be an alternative therapeutic option for DBD.  相似文献   

8.
目的: 研究低体温与自主神经功能变化的关系。方法: 采用体表物理降温法逐步降低直肠温度,直肠温度变化范围为19-37 ℃。分别记录不同直肠温度下大鼠动态心电和血压信号。应用心率变异性和血压变异性分析系统评价低体温对心率变异性和收缩压变异性的影响。结果: 心率变异分析表明,直肠温度下降到29 ℃以下,R-R间期均延长(P<0.01),提示心率明显降低;当直肠温度下降到19-21 ℃时,心率变异归一化低频功率降低(P<0.05)和归一化高频功率增加(P<0.05),而且自主神经的平衡向心迷走神经张力增强的方向发生了转移(P<0.05)。血压变异性分析表明,体温下降到31℃时与呼吸有关的归一化高频功率开始增加(P<0.01);直肠温度下降到29 ℃以下(除27 ℃外),与呼吸有关的归一化高频功率增加(P<0.05或P<0.01),同时自主神经的平衡也发生了改变(P<0.05)。结论: 随着体温的降低,心血管迷走神经活性增加,自主神经的平衡向迷走神经张力增强的方向转移。低体温对血压变异性的影响敏感于心率变异性。  相似文献   

9.
Prostaglandins (PGs) are well known as one of the chemical mediators of inflammation. Nonsteroidal anti-inflammatory drugs (NSAIDs), PG synthesis inhibitors, are used for anti-nociception and/or anti-inflammation. We examine the effect of loxoprofen, an NSAID, on micturiton in acetic acid-induced bladder inflammation of the rats. In cystometrogram study with saline infusion into the urinary bladder, loxoprofen did not alter the interval of bladder contraction (IC, 107% of the control). IC was shortened by acetic acid infusion (65% of the control) and loxoprofen prolonged the IC (162% of acetic acid infused period). This prolonged IC was approximately same as the control. Loxoprofen did not alter the threshold pressure and the maximal voiding pressure. These data suggest that PGE2 might not play a part of normal micturition and may play a part of the micturition reflex during acetic acid infusion. That is, loxoprofen might be useful for pathological hyperreflex of the micturition.  相似文献   

10.
心室复极化时程与自主神经系统关系的研究   总被引:2,自引:0,他引:2  
目前,随着心血管疾病日益增多,国外有少量研究者开始分析心室极化时程变异(Repolariztion duration variability,RDV)某些心脏疾病会在心室复极化时程上会有所表现。我们用乌拉坦麻醉大白鼠,研究用阿托品阻断迷走神经前后,RDV的变化规律。通过正常人体位变化来改变人体自主神经系统的平衡状态,以研究心室复极化时程与自主神经系统的关系,发现大白鼠的HRV和RDV的谱分析的峰值  相似文献   

11.
Normal voiding needs a coordinated, sustained bladder contraction of adequate size and duration. It requires a decrease in resistance of the bladder neck and urethra and no obstruction. Voiding problems can arise from abnormal storage of urine or problems with urinary control. The aim of this article was to review the functional anatomy and physiology of urinary control and micturition and the pathophysiology of urinary control problems. The Medline (PubMed) database, Cochrane Library, and Science Citation Index were searched electronically to identify original published studies on bladder anatomy, function and urinary control. References were searched from relevant chapters in specialized texts and all were included. Voiding problems are the most common presenting urological symptoms in general medical practice. Urinary incontinence occurs when the normal process of storing and passing urine is disrupted. A history of coexisting fecal incontinence suggests a neuropathic etiology. A better understanding of the physiology of urinary control could lead to preventive measures for postoperative urinary retention and incontinence such as fluid restriction and to appropriate anesthesia/analgesia, autonomic nerve preservation, total mesorectal excision (TME) for rectal cancer, and biofeedback exercises. It could also suggest appropriate therapeutic measures for established urinary incontinence. Clin. Anat., 2018. © 2018 Wiley Periodicals, Inc.  相似文献   

12.
目的研究糖尿病大鼠膀胱结构功能的改变及其肾上腺素能α1受体及其亚型的表达改变,并探讨其意义。方法采用1%链脲佐菌素(STZ)建立糖尿病大鼠的模型,实验分为正常对照组和糖尿病组。分别于2周、4周、6周进行在体充盈性膀胱测压评估膀胱功能,处死动物后取膀胱组织标本常规HE染色观察膀胱逼尿肌病理组织学变化,并采用Western blot与免疫荧光检测α1受体亚型(α1A受体与α1D受体)的表达改变。结果糖尿病大鼠体重减轻,尿量和膀胱湿重增加;充盈性膀胱测压检查结果显示糖尿病大鼠膀胱容量、顺应性、逼尿肌压力上升,残余尿量明显增加,排尿效率明显降低;常规HE染色光镜下观察可见糖尿病大鼠膀胱逼尿肌肌束进行性结构松散、紊乱,甚至出现肌束断裂。Western blott结果显示α1A受体及α1D受体的表达在逼尿肌中表达量随病程进行性下降,糖尿病组与正常对照组间对比差异有统计学意义。免疫荧光结果显示糖尿病膀胱实验组α1A受体和α1D受体灰度值均较相应对照组减少,且随病程进行性减少。结论糖尿病大鼠早期即可出现膀胱逼尿肌形态学和功能的改变,糖尿病膀胱中的α1-AR表达存在负相关关系,提示糖尿病可引起膀胱部位α1-AR表达减少。α1-AR表达减少可能是引起糖尿病膀胱顺应性增加,残余尿量增加的影响因素之一。  相似文献   

13.
Physiological and anatomical investigations are commonly combined in experimental models. When studying the lower urinary tract (LUT), it is often of interest to perform both urodynamic studies and retrogradely labeled neurons innervating the peripheral target organs. However, it is not known whether the use of anatomical tracers for the labeling of, e.g. spinal cord neurons may interfere with the interpretation of the physiological studies on micturition reflexes. We performed cystometry and external urethral sphincter (EUS) electromyography (EMG) under urethane anesthesia in adult female rats at 5–7 days after injection of a 5% fluorogold (FG) solution or vehicle into the major pelvic ganglia (MPG) or the EUS. FG and vehicle injections into the MPG and EUS resulted in decreased voiding efficiency. MPG injections increased the duration of both bladder contractions and the inter-contractile intervals. EUS injections decreased EUS EMG bursting activity during voiding as well as increased both the duration of bladder contractions and the maximum intravesical pressure. In addition, the bladder weight and size were increased after either MPG or EUS injections in both the FG and vehicle groups. We conclude that the injection of anatomical tracers into the MPG and EUS may compromise the interpretation of subsequent urodynamic studies and suggest investigators to consider experimental designs, which allow for physiological assessments to precede the administration of anatomical tracers into the LUT.  相似文献   

14.
Continuous cystometry at two filling rates (50 and 100 ml min-1) and stepwise cystometry (successive rapid volume infusions followed by bladder wall relaxation) were performed in 12 healthy subjects. Suprapubic catheters were used for infusion and recording of perivesical and intravesical pressures. The continuous cystometrograms obtained at filling rates of 50 and 100 ml min-1, respectively, did not differ with respect to desire to void, transmural pressure increase or bladder capacity. Stepwise cystometry allowed the bladders to be filled to a slightly larger volume than during continuous cystometry, but with comparatively lower transmural pressures only at very large distension of the bladder. There was considerable inter-individual variation in transmural pressure at both continuous and stepwise cystometry. Stepwise cystometry did not appear to provide any important additional information about pressure-volume relationship in the normal human bladder than could be obtained at routine clinical cystometry.  相似文献   

15.
The purpose of these experiments is to see if reflex nervous hyperventilation obtained by passive limb movements in man is a consequence of the activation of a direct ascending nervous pathway from mechanoreceptors of moving limbs to respiratory centres, or if it is the consequence of a primary enhanced cardiodynamic activity. Contemporaneous measurements of pulmonary ventilation and cardiac output (the latter with the trasthoracic bioimpedance method) were carried out in subjects whose ankles were passively moved at an angle of 10° and a frequency of 1 Hz, each test lasting three breaths. Results showed a fast increse in pulmonary ventilation in all test breaths (+27% from control) mainly depending on respiratory frequency increases and accompanied by a tendency to reduce end tidal PCO2. Cardiac output did not change during tests because of a lack of changes in heart rate and stroke volume. The lack of cardiac output increases during this reflex hyperventilation supports the existence of a direct neural pathway from limb proprioreceptor afferents to respiratory structures.  相似文献   

16.
A functional impairment of the bladder and heart in a decompensated state caused by a pressure overload is accompanied by a decrease in the sarcoplasmic reticulum Ca2+-ATPase (SERCA2). The beneficial effects of SERCA2 overexpression in preserving cardiac functions have been previously reported. The aim of the present study was to investigate the effects of overexpressed SERCA2 on bladder functions under physiological and pathological conditions using partial bladder outlet obstruction (BOO) in SERCA2a transgenic Wistar rats (TG). Bladder cystometry and western blot analysis were performed using the wild-type Wistar rats (WT), TG, and BOO models (WTBOO and TGBOO). Persistent overexpression of SERCA2 induces reduced bladder compliance without hypertrophy in TG. BOO induces reduced bladder compliance and hypertrophy in WT and TG in the sub-acute phase, but persistent overexpression of SERCA2a in TG does not aggravate the bladder compliance and hypertrophy. In conclusion, SERCA2a overexpression affects bladder functions under physiological conditions, but not in BOO-induced sub-acute pathological conditions.  相似文献   

17.
Heart rate variability analysis is a dynamic method to estimate the autonomic control over the cardiac cycle. Although dysfunction in this control system may appear spontaneously, other deficits may require provocation of the system. In this article we describe a non-invasive method to perturb the autonomic influences on the cardiac cycle. We recorded the ECG and respiratory pressure of ten healthy volunteers while introducing a random forced oscillation pressure wave onto spontaneous respiration. The heart period time series was determined and the power spectra for the 0.05–0.15, 0.15–0.3 and 0.05–0.4 Hz bands were calculated. The random input did not alter mean heart rate. However, the segments with the forced oscillation input demonstrated, on average, a tenfold increase in spectral power averaged across all subjects, with a maximum observed effect of 100-fold increase in power. This increase in power correlated with the respiratory frequency. This study demonstrates that random noise ventilation, such as used in respiratory forced oscillation impedance estimates, significantly alters the autonomic input to cardiac cycle variability in wake subjects.  相似文献   

18.
To explore whether depth of sleep is related to changes in autonomic control in rats, continuous power-spectral analysis of electroencephalogram (EEG) and heart rate variability (HRV) was performed in unanesthetized rats during normal daytime sleep. Quiet sleep (QS) was associated with an increase in high-frequency power of HRV (0.6-2.4 Hz, HF) but a decrease in low-frequency power (0.06-0.6 Hz) to HF ratio (LF/HF) compared with awakening. During QS, LF/HF was significantly and negatively correlated with delta power of EEG (0.5-4.0 Hz), whereas mean R-R interval and HF were not. As in humans, cardiac sympathetic regulation in rats is negatively related to the depth of sleep during QS, although vagal regulation is not. Our methodology offers a parallel way of studying the interaction between cerebral cortical and autonomic functions in rats.  相似文献   

19.
The autonomic nervous system innervates every organ in the body. Since autonomic disturbances affect patient survival, an understanding and recognition of these disturbances are important. We adopted several new methods to evaluate autonomic function accurately. 123I-metaiodobenzylguanidine scintigraphy can assess the cardiac autonomic function even in the presence of cardiac arrhythmia. Laser-Doppler flowmetry, ultrasonographic study in the vessels and near-infrared spectrophotoscopy techniques serve as useful markers for screening the dysfunction of vasomotor neurons and blood circulation. Electrogastrography and the circadian rhythms of protein C secretion could be markers of the visceromotor nerves in the abdomen. Electrogastrography is a particularly useful tool for reflecting on functional changes in gastrointestinal motility. The evaluation of anemia could be a marker of autonomic dysfunction in the kidney and bone marrow in patients with familial amyloidotic polyneuropathy, pandysautonomia, and multiple system atrophy. Normocytic and normochromic anemia correlated with the severity of autonomic dysfunction were shown in these patients. We also evaluated the dysfunction of the neuroendocrine system and sudomotor neuron using our new autonomic function tests. The glucose-tolerance test could become one of the most useful clinical tools for detecting autonomic dysfunction in the endocrine system. Microhydrography and thermography could be useful tools for diagnosing the lesion site of dyshidrosis. Moreover, it is clinically important to check the systemic circulation and autonomic function in patients treated with sildenafil citrate and organ transplantation to save their lives. Our new autonomic function tests, such as laser-Doppler flowmetry and 123I-metaiodobenzylguanidine scintigraphy, are crucial tools in supplying the best symptomatic treatment for such patients.  相似文献   

20.
背景:干细胞增殖和分化形成成纤维细胞以及适当的结缔组织,从而实现组织的再生,治疗自体盆腔器官脱垂和压力性尿失禁是目前该领域的一个研究热点。 目的:观察自体脂肪源性干细胞与成纤维细胞治疗压力性尿失禁的可行性。 方法:建立压力性尿失禁大鼠模型,建模后1个月行自体脂肪源干细胞与成纤维细胞尿道周围注射,细胞移植后1个月测定大鼠腹压漏尿点压力,同时近端尿道组织采用苏木精-伊红染色、弹力纤维染色观察形态学改变。 结果与结论:干细胞治疗后的模型大鼠漏尿点压力升高(P < 0.01),膀胱排空正常。尿道壁肌层增厚(P < 0.01),弹力纤维、平滑肌含量增多(P < 0.01)。结果证实,自体脂肪源性干细胞与成纤维细胞联合尿道周围注射能明显提高压力性尿失禁大鼠腹压漏尿点压力,增强注射点尿道肌层压力,可用于压力性尿失禁的治疗。  相似文献   

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