Catheter ablation is increasingly used to treat patients with atrial fibrillation (AF). Ablation of ganglionic plexi is often performed to reduce vagal innervation and has been shown to confer a better long-term outcome in terms of AF recurrence. We report a case of a patient having AF ablation with a profound ...
PubMed Central
A 15-year-old female patient presented with frequent episodes of vasovagal syncope refractory to non-pharmacological and pharmacological measures. Two tilt-table tests performed before and after conventional therapy were positive and reproduced the patient's clinical symptoms. Selective vagal denervation, guided by HFS, was performed. Six radiofrequency ...
PubMed
Aims Neurally meditated reflex or neurocardiogenic or vasovagal syncope (NMS) is usually mediated by a massive vagal reflex. This study reports the long-term outcome of NMS therapy based on endocardial radiofrequency (RF) catheter ablation of the cardiac vagal nervous system aiming permanent attenuation or elimination of the ...
Acid secretion in pavlov pouches in dogs is known to increase after antrectomy in response to histamine and gastrin. Dogs with gastric fistulae were tested with histamine and tetragastrin as a control study. The vagal nerve fibers to the antrum were divid...
National Technical Information Service (NTIS)
35 unanesthetized decerebrate cats and 10 intact cats under chloralose were prepared with denervation of both carotid sinuses, section of the right vago-aortic trunk and of the left aortic nerve. Efferent vagal activity being blocked by atropine, the affe...
Experimental denervation in animals has shown that carotid baro- and chemoreceptors play an eminent role in maintaining blood pressure and blood gas homeostasis. Denervation of carotid sinus baro- and chemoreceptors in humans may occur as a complication of invasive interventions on the neck or after experimental surgical treatment in asthma. In this ...
1. The effect of cocaine has been studied on vagal escape and on the tachycardia due to vagal stimulation in the atropinized dog. All the dogs were submitted to acute cervical section of the spinal cord and acute or chronic sympathetic denervation. 2. Cocaine, 5 mg/kg or 40 ?g/kg/min, I.V., induces a significant enhancement of the ...
The ECL cells in the oxyntic mucosa secrete histamine in response to gastrin, stimulating parietal cells to produce acid. Do they also operate under nervous control? The present study examines histamine mobilization from rat stomach ECL cells in situ in response to acute vagal excitation and to food or gastrin following vagal or sympathetic ...
Changes in intragastric pressure after dorsal truncal vagotomy, investigated by stimulation of the surviving vagal branches and by step inflation of the stomach, were divided into an early phase lasting five days, and a late phase continuing for at least three months. During the early phase the amplitude of vagal evoked contraction was diminished but the ...
Sympathetic and parasympathetic function and somatic nerve conduction were assessed in ten patients with diphtheritic neuropathy and 28 controls. None of the patients had postural hypotension. The Valsalva ratio was abnormal in two patients who also had myocarditis, but it was normal in five cases. Cardiac vagal dysfunction was found in five patients. One case showed cardiac ...
We conducted several experiments that focused on the effect of vagal control on mucociliary clearance (MCC) in murine lungs. We hypothesized that loss of vagal control by chronic denervation (i.e. vagotomy) would reduce both basal MCC and the increase in MCC typically observed upon stimulation of capsaicin sensitive C-fibers. Vagotomy ...
The pathophysiology of resistant hypertension is complex. Activation of the sympathetic nervous system has been suggested to be one of the main contributors for maintenance of blood pressure elevation and the development of comorbidities. Catheter-based renal denervation - by ablation of the efferent and afferent renal sympathetic nerves - is a new ...
Skeletal muscle atrophy occurs in a variety of clinical settings, including cachexia, disuse, and denervation. Inflammatory cytokines have been shown to be mediators of cancer cachexia; however, the role of cytokines in denervation- and immobilization-induced skeletal muscle loss remains unknown. In this study, we demonstrate that a single cytokine, ...
the sinus node,7,8,14 and a third fat pad between the superior vena cava and the aorta contains more the fat pad near the pulmonary veins and superior vena cava, sufficient to cause partial denervation the right pulmonary veins and superior vena cava, and ablation in this location, especially if more ex
E-print Network
We used microdialysis to monitor local gastrin release in response to food, acid blockade and acute vagal excitation. For the first time, gastrin release has been monitored continuously in intact conscious rats in a physiologically relevant experimental setting in a fashion that minimizes confounding systemic effects. Microdialysis probes were placed in the submucosa on either ...
Aims: The endovascular application of low-dose radiofrequency (RF) energy to the renal arteries results in effective ablation of sympathetic nerve fibres leading to a significant lowering of blood pressure (BP). This study aims to examine the feasibility and safety of renal denervation by the use of a standard electrophysiology (EP) catheter. Methods and ...
The systemic anti-inflammatory effect induced by antidromic sensory nerve stimulation was investigated in rats and guinea-pigs. In atropine-pretreated rats, bilateral antidromic stimulation of vagal afferent fibres (8 Hz, 20 min, at C-fibre strength) inhibited plasma extravasation induced by 1% mustard oil on the acutely denervated hindlegs by ...
Skeletal muscle wasting is a major human morbidity, and contributes to mortality in a variety of clinical settings, including denervation and cancer cachexia. In this study, we demonstrate that the expression level and autoubiquitination of tumor necrosis factor (?) receptor adaptor protein 6 (TRAF6), a protein involved in receptor-mediated activation of several signaling ...
The enteric nervous and enteroendocrine systems regulate different processes in the small intestine. Ablation of myenteric plexus with benzalkonium chloride (BAC) stimulates epithelial cell proliferation, whereas endocrine serotonin cells may inhibit the process. To evaluate the connection between the systems and the influence of myenteric plexus on serotoninergic cells in ...
Parallel increments of gastric acid and pepsinogen secretion generally occur after the application of cholinergic stimuli. However, it still remains to be established whether the changes in acid output associated with cholinergic stimulation play a role in regulation of the concomitant peptic secretory activity. In the present study, an anesthetized rat model was used for the evaluation of ...
AimsThe parasympathetic nervous system is thought to play a key role in atrial fibrillation (AF). Since parasympathetic signalling is primarily mediated by the heterotrimeric G-protein, G?i??, we hypothesized that targeted inhibition of G?i interactions in the posterior left atrium (PLA) would modify the substrate for vagal ...
Specific, high affinity Ang II binding in the dog's dorsal medulla is concentrated in the area postrema, nucleus tractus solitarii (nTS) and dorsal motor nucleus of the vagus (dmnX). More recently Ang II binding sites were observed where bundles of vagal afferent fibers enter the dorsal medulla 6 mm rostral to obex and in the nodose ganglia and peripheral ...
Energy Citations Database
Vasoactive Intestinal Peptide (VIP) neurons are maturing during suckling and weaning periods and the neuropeptide VIP is thought to be neurotrophic during ontogenesis. We have previously demonstrated that suckling rats with myenteric ablation have significantly higher mitotic index and an increase on villus height and crypt depth 15 days after treatment. In the current study, ...
BACKGROUND: Pharmacological and ablative therapies for atrial fibrillation (AF) have suboptimal efficacy. Newer gene-based approaches that target specific mechanisms underlying AF are likely to be more efficacious in treating AF. Parasympathetic signaling appears to be an important contributor to AF substrate. OBJECTIVE: To develop a non-viral gene-based strategy to ...
Three patients with extensive retroperitoneal cancer are presented, in whom the psoas muscle was resected as part of a radical tumor excision. The resection of the psoas muscle, including the femoral nerve, which travels in its substance, and the genitofemoral and ilioinguinal nerves, caused little morbidity (denervation weakness of the quadriceps and anterior high numbness) ...
There is evidence that parasympathetic denervation may prevent atrial fibrillation (AF) recurrences. This study aimed at applying an anatomic approach for ablation of atrial ganglionic plexi (GPs) in patients with paroxysmal AF. Nineteen patients with symptomatic, paroxysmal AF underwent anatomically guided radiofrequency ablation at ...
PURPOSE OF REVIEW: Despite the abundance of antihypertensive drugs, resistant hypertension remains a major clinical problem. Recent technological advances render interventional management of resistant hypertension one of the hottest topics in the hypertension field. The aim of this review is to present the pathophysiologic background and the mechanisms mediating blood pressure reduction after ...
Niijima previously reported that intragastric infusion of glutamate has increased the activity of the efferent parasympathetic nerves that innervate the stomach and pancreas in urethane-anesthetized rats. In the present study, the effects of intragastric injection of glutamate on the efferent sympathetic nerve outflow to the kidney and the white adipose tissue in rats were analyzed. Although the ...
This study investigated how baro- and chemoreceptor afferents interact with emetic signals from gastric afferents and the vestibular system, and how these interactions modulate emetic and prodromal responses. We performed splanchnic denervation and abdominal vagotomy in anesthetized shrews (Suncus murinus), and then induced emetic responses by gastric distension. Next, we ...
The objective of this study was to examine the effects of two different denervation procedures on the distribution of nerve fibers and neurotransmitter levels in the rat jejunum. Extrinsic nerves were eliminated by crushing the mesenteric pedicle to a segment of jejunum. The myenteric plexus and extrinsic nerves were eliminated by serosal application of the cationic surfactant ...
BACKGROUND: Renal sympathetic hyperactivity is associated with hypertension, a leading cause of mortality worldwide. Renal sympathetic denervation via the Symplicity Catheter System has been shown to decrease blood pressure by 33/11�mmHg by 6�months, with no radiofrequency (RF)-related adverse sequelae visible by CT/MR angiography or renal duplex ultrasound 6�months ...
Renal sympathetic hyperactivity is seminal in the maintenance and progression of hypertension. Catheter-based renal sympathetic denervation has been shown to significantly reduce blood pressure (BP) in patients with hypertension. Durability of effect beyond 1 year using this novel technique has never been reported. A cohort of 45 patients with resistant hypertension (systolic ...
Ganglionated plexus (GP) ablation has been shown effective for eliminating atrial fibrillation (AF), the most common clinical tachyarrhythmia. However, the safety of destroying the main cardiac autonomic structures remains unclear. This study investigated the acute effects of GP ablation on the sinoatrial nodal (SAN) and atrioventricular nodal (AVN) ...
The incretin and food intake suppressive effects of intraperitoneally administered glucagon-like-peptide-1 (GLP-1) involve activation of GLP-1 receptors (GLP-1R) expressed on vagal afferent fiber terminals. CNS processing of GLP-1R-driven vagal afferents results in satiation signaling, and enhanced insulin secretion from pancreatic-projecting ...
As much as one third of patients with arterial hypertension are treatment refractory as they do not reach sufficient blood pressure control despite antihypertensive combination therapy of significant duration. In patients with therapy-resistant hypertension, the kidneys play a central role as activator of the sympathetic nervous system. Sympathetic nervous activation via efferent nerve fibers ...
Monosodium l-glutamate (MSG) is a substance known to produce the umami taste. Recent studies indicate that MSG also stimulates a variety of activities in the gastrointestinal tract through its receptor in the gut, but no study has reported the activity in conscious large experimental animals. The aim of our study was to investigate whether direct intragastric MSG stimulates gut motility and to ...
BACKGROUND: -Autonomic denervation may suppress atrial fibrillation (AF) vulnerability. This study was designed to assess the short-to-mid term effects of botulinum toxin, a cholinergic neurotransmission blocker, on AF inducibility. METHODS AND RESULTS: -A total of 23 mongrel dogs were studied. The sinus node and AV node epicardial fat pads were exposed through a right lateral ...
Essential hypertension remains one of the biggest challenges in medicine with an enormous impact on both individual and society levels. With the exception of relatively rare monogenetic forms of hypertension, there is now general agreement that the condition is multifactorial in nature and hence requires therapeutic approaches targeting several aspects of the underlying pathophysiology. ...
Aims To verify whether spectral components of atrial electrograms (AE) during sinus rhythm (SR) correlate with cardiac ganglionated plexus (GP) sites. Methods and results Thirteen patients undergoing atrial fibrillation (AF) ablation were prospectively enrolled. Prior to radio frequency application, endocardial AE were recorded with a sequential point-by-point approach. ...
... The kidneys were studied with intact renal nerves, after denervation, and following denervation plus infusion of phentolamine. ...
DTIC Science & Technology
The autonomic nervous system plays a major role in blood pressure regulation and pathogenesis of essential hypertension. Before the advent of orally active antihypertensive treatments, surgical sympathectomy was the only therapeutic option in severely hypertensive patients. It was effective in reducing blood pressure in half of these patients. However, this intervention was associated with high ...
The enteric nervous system plays a role on the stimulation of secretory cells of intestinal epithelia. We have demonstrated that ablation of ENS stimulates epithelial cell proliferation. As goblet cells are important constituents of the epithelial sheet, it is mandatory to investigate separately this cell type. The myenteric plexus of the ileum of rats in postnatal development ...
Incessant ventricular tachycardia and long-standing ectopic beats lead to tachycardia-induced cardiomyopathy. Catheter ablation eliminates ventricular tachycardia and reverses left ventricular (LV) dysfunction. 201-Thallium ((201)Tl) scintigraphy demonstrates perfusion defects with ischemic cardiomyopathy. Reversible perfusion defects are observed even in non-ischemic ...
Reflex effects of pulmonary C-fiber receptor stimulation by right atrial injections of capsaicin and lobeline were investigated in conscious monkeys (n=17). Capsaicin injection (15.0+/-1.4 microg/kg) produced apnea mostly (n=15, latency-1.7+/-0.2 s) and bradycardia, which were abolished by vagotomy (n=4). Lobeline administration (142+/-6 microg/kg) produced either apnea (n=7, latency -2.0+/-0.3 s) ...
The acute ventilatory response to inhalation of wood smoke was studied in 58 anesthetized Sprague-Dawley rats. Wood smoke ([approximately]6 ml) was inhaled spontaneously via a tracheal cannula. Within the first two breaths of smoke inhalation, either a slowing of respiration (SR) (n=39) or an augmented inspiration (AI) (n=19) was elicited consistently in each rat. The SR was primarily due to a ...
In anesthetized male rats, infusion of glutamine (2 mumol/min) into the superior mesenteric vein at a rate known to induce liver cell swelling leads to marked decreases in renal glomerular filtration rate, renal para-aminohippurate clearance and urinary flow rate. Glutamine infused at identical rates into the jugular vein does not elicit any of these effects. The effect of glutamine is mimicked by ...
1. Drug-induced membrane current fluctuations were analysed at frog ectopic neuromuscular junctions formed de novo by somatic motoneurones and by preganglionic autonomic neurones of the vagus nerve, and at denervated end-plates reinnervated by the vagus nerve. 2. At ectopic motor end-plates, the mean open time of the ion channels activated by ACh is tau ACh = 1.8 +/- 0.1 msec ...