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The Journal of Physiology Mar 1949
Topics: Animals; Aorta; Aortic Bodies; Cats
PubMed: 18128172
DOI: No ID Found -
The Journal of the Louisiana State... 2012Paragangliomas are tumors of the sympathetic and parasympathetic paraganglia. While most paraganglioma are of parasympathetic origin and present as benign palpable... (Review)
Review
Paragangliomas are tumors of the sympathetic and parasympathetic paraganglia. While most paraganglioma are of parasympathetic origin and present as benign palpable masses of the neck, sympathetic paraganglioma are often secretory, presenting with symptoms related to excess catecholamines. Such symptoms include hypertension, headache, palpitations, and diaphoresis. Most sympathetic paraganglioma form within the adrenal medulla, the largest sympathetic paraganglia, and are commonly known as pheochromocytomas. However, sympathetic paragangliomas may present extra-adrenally, carrying a significantly higher risk of malignancy. In this manuscript, we examine a case of a young man with an extra-adrenal sympathetic paraganglioma of the Organ of Zuckerkandl. Furthermore, we discuss appropriate diagnostic workup and treatment of pheochromocytomas and sympathetic paragangliomas.
Topics: Aorta, Abdominal; Catecholamines; Dissection; Humans; Male; Monitoring, Physiologic; Para-Aortic Bodies; Paraganglioma; Preoperative Care; Prognosis; Radiography; Treatment Outcome; Young Adult
PubMed: 22533110
DOI: No ID Found -
Pediatrics International : Official... Mar 2018
Topics: Aneurysm, False; Aorta, Thoracic; Aortic Aneurysm, Thoracic; Bronchi; Child; Female; Foreign Bodies; Humans; Respiratory Aspiration
PubMed: 29436072
DOI: 10.1111/ped.13487 -
Journal of Applied Physiology... Jan 2004Peripheral chemoreceptors (carotid and aortic bodies) detect changes in arterial blood oxygen and initiate reflexes that are important for maintaining homeostasis during... (Review)
Review
Peripheral chemoreceptors (carotid and aortic bodies) detect changes in arterial blood oxygen and initiate reflexes that are important for maintaining homeostasis during hypoxemia. This mini-review summarizes the importance of peripheral chemoreceptor reflexes in various physiological and pathophysiological conditions. Carotid bodies are important for eliciting hypoxic ventilatory stimulation in humans and in experimental animals. In the absence of carotid bodies, compensatory upregulation of aortic bodies as well as other chemoreceptors contributes to the hypoxic ventilatory response. Peripheral chemoreceptors are critical for ventilatory acclimatization at high altitude. They also contribute in part to the exercise-induced hyperventilation, especially with submaximal and heavy exercise. During pregnancy, hypoxic ventilatory sensitivity increases, perhaps due to the actions of estrogen and progesterone on chemoreceptors. Augmented peripheral chemoreceptors have been implicated in early stages of recurrent apneas, congestive heart failure, and certain forms of hypertension. It is likely that chemoreceptors tend to maintain oxygen homeostasis and act as a defense mechanism to prevent the progression of the morbidity associated with these diseases. Experimental models of recurrent apneas, congestive heart failure, and hypertension offer excellent opportunities to unravel the cellular mechanisms associated with altered chemoreceptor function.
Topics: Altitude Sickness; Chemoreceptor Cells; Humans; Hypoxia; Oxygen
PubMed: 14660497
DOI: 10.1152/japplphysiol.00809.2003 -
Animals : An Open Access Journal From... Sep 2021Chemodectomas are low prevalence tumors with complex clinical management. Many present as an incidental finding however, in other dogs, they produce pericardial effusion...
Chemodectomas are low prevalence tumors with complex clinical management. Many present as an incidental finding however, in other dogs, they produce pericardial effusion and/or compression, leading to the appearance of severe clinical signs. There are currently several approaches: surgery, radiotherapy, stent placement and chemotherapy. This is the first description of percutaneous echo-guided radiofrequency ablation of aortic body tumors. This minimally invasive treatment is based on high frequency alternating electrical currents from an electrode that produces ionic agitation and generates frictional heat, causing coagulation necrosis. Five dogs with an echocardiographic and cytological diagnosis of chemodectoma underwent percutaneous echo-guided radiofrequency ablation. At the time of presentation, all the dogs showed clinical signs, such as ascites and/or collapse. There were no complications either during the procedure or in the following 24 hours. Rapid clinical improvement associated with a reduction in size and change in sonographic appearance of the mass were achieved with no complications. Six months follow-up was carried out in all dogs. A second percutaneous echo-guided RFA was performed eight months after the first procedure in one dog. Based on our experience, radiofrequency ablation seems to be a feasible and safe technique, making it a potential alternative therapeutic approach in the clinical management of aortic body tumors leading to severe clinical compromise.
PubMed: 34679812
DOI: 10.3390/ani11102790 -
Potential roles of ATP and local neurons in the monitoring of blood O2 content by rat aortic bodies.Experimental Physiology Jan 2014Aortic bodies are arterial chemoreceptors presumed to monitor blood O2 content by unknown mechanisms, in contrast to their well-studied carotid body counterparts, which...
Aortic bodies are arterial chemoreceptors presumed to monitor blood O2 content by unknown mechanisms, in contrast to their well-studied carotid body counterparts, which monitor PO2 and /pH. We recently showed that rat aortic body chemoreceptors (type I cells), located at the left vagus-recurrent laryngeal nerve bifurcation, responded to PO2 and PCO2 /pH in a manner similar to carotid body type I cells. These aortic bodies are uniquely associated with a group of local neurons, which are also sensitive to these stimuli. Here, we hypothesized that these local neurons may contribute to monitoring blood O2 content. During perforated patch recordings, ATP, known to be released from (carotid body) type I cells and red blood cells during hypoxia, induced inward currents and excited ≈ 45% of local neurons (EC50 ≈ 1 μm), mainly via heteromeric P2X2/3 purinoceptors. While ATP also induced a rise in intracellular [Ca(2+)] in a subpopulation of these neurons, almost all of them responded to nicotinic cholinergic agonists. During paired recordings, several juxtaposed neurons showed strong bidirectional electrical coupling, suggesting a local co-ordination of electrical activity. Perfusion with Evans Blue dye resulted in labelling of aortic body paraganglia, suggesting they have ready access to circulatory factors, e.g. ATP released from red blood cells during hypoxia. When combined with confocal immunofluorescence, the dye-labelled regions coincided with areas containing tyrosine hydroxylase-positive type I cell clusters and P2X2-positive nerve endings. We propose a working model whereby local neurons, red blood cells, ATP signalling and low blood flow contribute to the unique ability of the aortic body to monitor blood O2 content.
Topics: Adenosine Triphosphate; Animals; Aortic Bodies; Calcium; Cells, Cultured; Erythrocytes; Hypoxia; Neurons; Oxygen; Rats; Receptors, Purinergic P2X2; Receptors, Purinergic P2X3; Tyrosine 3-Monooxygenase
PubMed: 24097160
DOI: 10.1113/expphysiol.2013.075408 -
Brain Research Dec 1979
Topics: Acetylcholine; Animals; Aortic Bodies; Carbon Dioxide; Carbon Monoxide; Carboxyhemoglobin; Carotid Body; Cats; Chemoreceptor Cells; Neurons; Oxygen; Paraganglia, Nonchromaffin
PubMed: 509229
DOI: 10.1016/0006-8993(79)90503-1 -
The Journal of Physiology Nov 2016In humans, excitation of peripheral chemoreceptors with systemic hypoxia causes hyperventilation, hypertension and tachycardia. However, the contribution of particular... (Randomized Controlled Trial)
Randomized Controlled Trial
KEY POINTS
In humans, excitation of peripheral chemoreceptors with systemic hypoxia causes hyperventilation, hypertension and tachycardia. However, the contribution of particular chemosensory areas (carotid vs. aortic bodies) to this response is unclear. We showed that selective stimulation of the carotid body by the injection of adenosine into the carotid artery causes a dose-dependent increase in minute ventilation and blood pressure with a concomitant decrease in heart rate in conscious humans. The ventilatory response was abolished and the haemodynamic response was diminished following carotid body ablation. We found that the magnitude of adenosine evoked responses in minute ventilation and blood pressure was analogous to the responses evoked by hypoxia. By contrast, opposing heart rate responses were evoked by adenosine (bradycardia) vs. hypoxia (tachycardia). Intra-carotid adenosine administration may provide a novel method for perioperative assessment of the effectiveness of carotid body ablation, which has been recently proposed as a treatment strategy for sympathetically-mediated diseases.
ABSTRACT
Stimulation of peripheral chemoreceptors by acute hypoxia causes an increase in minute ventilation (VI), heart rate (HR) and arterial blood pressure (BP). However, the contribution of particular chemosensory areas, such as carotid (CB) vs. aortic bodies, to this response in humans remains unknown. We performed a blinded, randomized and placebo-controlled study in 11 conscious patients (nine men, two women) undergoing common carotid artery angiography. Doses of adenosine ranging from 4 to 512 μg or placebo solution of a matching volume were administered in randomized order via a diagnostic catheter located in a common carotid artery. Separately, ventilatory and haemodynamic responses to systemic hypoxia were also assessed. Direct excitation of a CB with intra-arterial adenosine increased VI, systolic BP, mean BP and decreased HR. No responses in these variables were seen after injections of placebo. The magnitude of the ventilatory and haemodynamic responses depended on both the dose of adenosine used and on the level of chemosensitivity as determined by the ventilatory response to hypoxia. Percutaneous radiofrequency ablation of the CB abolished the adenosine evoked respiratory response and partially depressed the cardiovascular response in one participant. The results of the present study confirm the excitatory role of purines in CB physiology in humans and suggest that adenosine may be used for selective stimulation and assessment of CB activity. The trial is registered at ClinicalTrials.gov NCT01939912.
Topics: Adenosine; Aged; Baroreflex; Carotid Body; Consciousness; Female; Hemodynamics; Humans; Hypoxia; Male; Middle Aged; Pulmonary Ventilation
PubMed: 27435894
DOI: 10.1113/JP272109 -
The Journal of Veterinary Medical... Jun 2005Unusual metastasis of malignant aortic body tumor to multiple bones was detected in a 5-year-old female English Setter dog. Radiographs exhibited an abnormal mass in the...
Unusual metastasis of malignant aortic body tumor to multiple bones was detected in a 5-year-old female English Setter dog. Radiographs exhibited an abnormal mass in the base of heart and osteolytic lesions in the bodies of T11 and L2 vertebrates, body of right femur, right proximal humoral epiphysis and infraspinous fossa near to the neck of right scapula. At necropsy, multiple tumor masses of various sizes were observed also in the bones as well as the heart base and tracheobronchial lymph node. Tumor masses of L2 and T11 protruded into the vertebral canal and compressed corresponding sites of spinal cord, leading to paraplegia. Histopathologically, the tumor cells, arranged in sheets or nests, were polyhedral, lightly eosinophilic, finely granular cytoplasm with mostly round to oval nucleus and had scattered bizarre giant cells. Ultrastructural study revealed the characteristic findings that tumor cells contained a large number of small, electron-dense, membrane-limited secretory granules in cytoplasm. This is thought to be an extremely rare case having multiple bone metastases of a malignant aortic body tumor.
Topics: Animals; Aortic Bodies; Bone Neoplasms; Dog Diseases; Dogs; Fatal Outcome; Female; Microscopy, Electron, Transmission; Peripheral Nervous System Neoplasms
PubMed: 15997194
DOI: 10.1292/jvms.67.625 -
Veterinary Pathology 1972
Topics: Animals; Male; Paraganglioma, Extra-Adrenal; Rats; Rodent Diseases
PubMed: 4367413
DOI: 10.1177/030098587200900403