Pheochromocytoma as a Clinical Model of Peripheral Sympathetic Overdrive: Old and New Findings

AbstractPurpose of ReviewThe present paper will review the results of experimental and clinical studies aimed at defining the functional behavior of the central and peripheral nervous system in adrenal pheochromocytoma.Recent FindingsThe contribution of sympathetic neural influences to the development of high blood pressure values in pheochromocytoma is complex. Studies performed in experimental animal models have shown that hypertension and the concomitant high circulating levels of catecholamines can lead to inhibition of central sympathetic neural outflow by reflex mechanisms and direct stimulation of central adrenergic receptors, respectively. However, these studies have also shown that high circulating levels of catecholamines favor a downregulation of alpha- and beta-adrenergic receptors, lessening their response to endogenous and exogenous adrenergic stimulation. The present paper reviews results of human studies performed by our group and others on the behavior of the central and peripheral nervous system in human pheochromocytoma. We discuss data collected in patients with different levels of peripheral sympathetic drive, i.e., before and after surgical removal of the adrenal pheochromocytoma.SummaryIn the presence of elevated plasma catecholamine level, such as that characterizing adrenal pheochromocytoma, microneurography shows that central sympathetic neural activity is normal or even inhibited. At the peripheral vascular level, pheochromocytoma is characterized b...
Source: Current Hypertension Reports - Category: Primary Care Source Type: research

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Authors: Cornu E, Belmihoub I, Burnichon N, Grataloup C, Zinzindohoué F, Baron S, Billaud E, Azizi M, Gimenez-Roqueplo AP, Amar L Abstract Phaeochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumors that arise from the adrenal medulla or sympathetic and parasympathetic ganglia. These tumors produce most often catecholamines in excess, causing hypertension and sometimes severe acute cardiovascular complications. The diagnosis is based on plasma or urines metanephrines measurements and on conventional and nuclear medicine imaging. Catecholamines-producing PPGL is very unlikely if levels are nor...
Source: Revue de Medecine Interne - Category: Internal Medicine Tags: Rev Med Interne Source Type: research
Karel Pacak Pheochromocytomas and paragangliomas (PPGLs) are rare catecholamine-secreting neuroendocrine tumors of the adrenal medulla and sympathetic/parasympathetic ganglion cells, respectively. Excessive release of catecholamines leads to episodic symptoms and signs of PPGL, which include hypertension, headache, palpitations, and diaphoresis. Intraoperatively, large amounts of catecholamines are released into the bloodstream through handling and manipulation of the tumor(s). In contrast, there could also be an abrupt decline in catecholamine levels after tumor resection. Because of such binary manifestations of PP...
Source: Cancers - Category: Cancer & Oncology Authors: Tags: Review Source Type: research
Conclusions: Preliminary analysis suggests that there is an increase in HR and SBP after 60 minutes of PHE/TYR-containing amino acid administration which, in patients with PHEO/PGL, may represent increased sympathetic effects from temporarily boosted catecholamine biosynthesis. This is supported by the finding that increased HR and SPB is seen primarily in catecholamine secretors when using Clinisol but not with the 2.5% Lys/Arg solution. Other factors which may have contributed such as anxiety and nausea cannot be ruled out, although subgroup analysis suggests that these others factors alone does not account for the obser...
Source: Journal of Nuclear Medicine - Category: Nuclear Medicine Authors: Tags: Center for Therapy Excellence YIA Symposium Source Type: research
Conclusions: 68Ga-DOTA-NOC PET/CT shows higher sensitivity in the detection of bone metastasis and lymphadenopathy in PHEOs/PGLs, which has great merits for staging and risk stratification of PHEOs/PGLs. PRRT has good response especially in symptom release and improvement of living quality, and is tolerable with no evident hematological events and renal toxicity. Furthermore, present study will pave the way for SSA based theranostics on PHEOs/PGLs. Keywords: Pheochromocytomas, Paragangliomas, 68Ga-DOTA-NOC,131I-MIBG, Somatostatin Receptor Abbreviations: PHEO: Pheochromocytoma; PGL: Paraganglioma; MIBG: Metaiodobenzylguanid...
Source: Journal of Nuclear Medicine - Category: Nuclear Medicine Authors: Tags: Endocrinology (Clinical Therapy) Posters Source Type: research
Abstract Pheochromocytomas and sympathetic paragangliomas are rare catecholamine-secreting tumors and represent very rare causes of intracerebral hemorrhage in young, with only few cases reported. A 32-year-old man presented to our emergency department because of sudden onset of severe headache. He had a six months history of paroxysmal headache, palpitations and sweating. During examination he became somnolent and developed left-sided hemiplegia. A computed tomographic (CT) scan of the brain showed a right temporoparietal hematoma. He was admitted to the Clinic for Neurosurgery and hematoma was evacuated. The pat...
Source: Endokrynologia Polska - Category: Endocrinology Authors: Tags: Endokrynol Pol Source Type: research
Postmicturition syndrome refers to symptoms caused by overdistension of the bladder or micturition. Bladder paraganglioma is a rare neuroendocrine neoplasm, which arises from the chromaffin tissue of the sympathetic nervous system embedded in the muscle layer of the bladder wall. Clinical presentation of catecholamine-secreting paragangliomas may mimic that of hyperfunctioning adrenal pheochromocytoma. Typical symptoms such as sweating, palpitations, headache, nausea, hypertension, or flushing are due to catecholamine release and are related to micturition or bladder overdistension.
Source: Journal of the American Society of Hypertension - Category: Cardiology Authors: Tags: Clinical Case Presentation Source Type: research
Post-micturition syndrome refers to symptoms caused by over distension of the bladder or micturition. Bladder paraganglioma (BP) is a rare neuroendocrine neoplasm, which arises from the chromaffin tissue of the sympathetic nervous system embedded in the muscle layer of the bladder wall. Clinical presentation of catecholamine-secreting paragangliomas may mimic that of hyperfunctioning adrenal phaeochromocytoma. Typical symptoms such as sweating, palpitations, headache, nausea, hypertension or flushing are due to catecholamine release and are related to micturition or bladder over-distension.
Source: Journal of the American Society of Hypertension - Category: Cardiology Authors: Tags: Clinical Case Presentation Source Type: research
Conclusions: LMI1195, a novel F-18-labeled PET-tracer, is highly effective in detecting tumors of the adrenal medulla or the sympathetic trunk. High uptake in lesions and superb image quality promote its use as alternative to MIBG. Further potential applications (e.g. assessment of the sympathetic innervation of the heart) should be evaluated.
Source: Journal of Nuclear Medicine - Category: Nuclear Medicine Authors: Tags: First-in-Human & amp; New Human Applications Source Type: research
We describe a case of one of the largest documented pheochromocytomas resected in the United States, an 18-cm tumor in a patient who presented with exertional dyspnea, abdominal pain, constipation, weight loss, and intermittent hypertension. After biochemical and appropriate imaging workup, the patient underwent an open resection of the mass.
Source: In Vivo - Category: Research Authors: Tags: Clinical Studies Source Type: research
Conclusions: The mainstay of treatment for patients with PCC/PGLs is surgical. However, the tide may be turning with the discovery of new genes associated with PCC/PGLs that may shed light on oncometabolites utilized by these tumors. PMID: 29409060 [PubMed - as supplied by publisher]
Source: The Journal of Clinical Endocrinology and Metabolism - Category: Endocrinology Authors: Tags: J Clin Endocrinol Metab Source Type: research
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