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Pheochromocytoma
Pheochromocytoma is a rare tumor of the adrenal medulla composed of chromaffin cells and is part of the paraganglioma (PGL) family of tumors, being defined as an intra-adrenal PGL. These neuroendocrine tumors can be sympathetic, where they release catecholamines into the bloodstream which cause the most common symptoms, including hypertension (high blood pressure), tachycardia (fast heart rate), sweating, and headaches. Some PGLs may secrete little to no catecholamines, or only secrete paroxysmally (episodically), and other than secretions, PGLs can still become clinically relevant through other secretions or mass effect (most common with head and neck PGL). PGLs of the head and neck are typically parasympathetic and their sympathetic counterparts are predominantly located in the abdomen and pelvis, particularly concentrated at the organ of Zuckerkandl at the bifurcation of the aorta. Signs and symptoms The symptoms of a sympathetic pheochromocytoma are related to sympathetic n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraganglioma
A paraganglioma is a rare neuroendocrine tumour, neuroendocrine neoplasm that may develop at various body sites (including the head, neck, thorax and abdomen). When the same type of tumor is found in the adrenal gland, they are referred to as a pheochromocytoma. They are rare tumors, with an overall estimated incidence of 1 in 300,000. There is no test that determines benign from malignant tumors; long-term follow-up is therefore recommended for all individuals with paraganglioma. Signs and symptoms Most paragangliomas are asymptomatic, present as a painless mass, or create symptoms such as hypertension, tachycardia, headache, and palpitations. While all contain neurosecretory granules, only in 1–3% of cases is secretion of hormones such as catecholamines abundant enough to be clinically significant; in that case manifestations often resemble those of pheochromocytomas (intra-medullary paraganglioma). Genetics About 75% of paragangliomas are sporadic; the remaining 25% are here ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chromaffin Cell
Chromaffin cells, also called pheochromocytes (or phaeochromocytes), are neuroendocrine cells found mostly in the adrenal medulla, medulla of the adrenal glands in mammals. These cells serve a variety of functions such as serving as a response to stress, monitoring carbon dioxide and oxygen concentrations in the body, maintenance of respiration and the regulation of blood pressure. They are in close proximity to pre-synaptic sympathetic ganglia of the sympathetic nervous system, with which they communicate, and structurally they are similar to post-synaptic sympathetic neurons. In order to activate chromaffin cells, the Splanchnic nerves, splanchnic nerve of the sympathetic nervous system releases acetylcholine, which then binds to nicotinic acetylcholine receptors on the adrenal medulla. This causes the release of catecholamines. The chromaffin cells release catecholamines: ~80% of adrenaline (epinephrine) and ~20% of noradrenaline (norepinephrine) into systemic circulation for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyperhidrosis
Hyperhidrosis is a medical condition in which a person exhibits excessive perspiration, sweating, more than is required for the Thermoregulation, regulation of body temperature. Although it is primarily a physical burden, hyperhidrosis can deteriorate the quality of life of the people who are affected, frequently leading to psychological, physical, and social consequences. Hyperhidrosis can lead to difficulties in professional fields, with more than 80% of patients experiencing moderate to severe emotional effects from the disease. This excess of sweat happens even if the person is not engaging in tasks that require muscular effort, and it does not depend on the exposure to heat. Common places to sweat can include underarms, face, neck, back, groin, feet, and hands. It has been called by some researchers 'the silent handicap'. Both ''diaphoresis'' and ''hidrosis'' can mean either ''perspiration'' (in which word sense, sense they are synonymous with ''sweating'') or ''excessive per ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Organ Of Zuckerkandl
The organ of Zuckerkandl is a chromaffin body derived from the neural crest located at the bifurcation of the aorta or at the origin of the inferior mesenteric artery. It can be the source of a paraganglioma. The term para-aortic body is also sometimes used to describe it, as it usually arises near the abdominal aorta, but this term can be the source of confusion, because the term "corpora paraaortica" is also used to describe the aortic body, which arises near the thoracic aorta. This diffused group of neuroendocrine sympathetic fibres was first described by Emil Zuckerkandl, a professor of anatomy at the University of Vienna, in 1901. Some sources equate the " aortic bodies" and "paraaortic bodies", while other sources explicitly distinguish between the two. When a distinction is made, the "aortic bodies" are chemoreceptors which regulate circulation, while the "paraaortic bodies" are the chromaffin cells which manufacture catecholamines. Organs of Zuckerkandl (O of Z) harbor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catecholamines
A catecholamine (; abbreviated CA), most typically a 3,4-dihydroxyphenethylamine, is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine. Catechol can be either a free molecule or a substituent of a larger molecule, where it represents a 1,2-dihydroxybenzene group. Catecholamines are derived from the amino acid tyrosine, which is derived from dietary sources as well as synthesis from phenylalanine. Catecholamines are water-soluble and are 50% bound to plasma proteins in circulation. Included among catecholamines are epinephrine (adrenaline), norepinephrine (noradrenaline), and dopamine. Release of the hormones epinephrine and norepinephrine from the adrenal medulla of the adrenal glands is part of the fight-or-flight response. Tyrosine is created from phenylalanine by hydroxylation by the enzyme phenylalanine hydroxylase. Tyrosine is also ingested directly from dietar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Catecholamine
A catecholamine (; abbreviated CA), most typically a 3,4-dihydroxyphenethylamine, is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine. Catechol can be either a free molecule or a substituent of a larger molecule, where it represents a 1,2-dihydroxybenzene group. Catecholamines are derived from the amino acid tyrosine, which is derived from dietary sources as well as synthesis from phenylalanine. Catecholamines are water-soluble and are 50% bound to plasma proteins in circulation. Included among catecholamines are epinephrine (adrenaline), norepinephrine (noradrenaline), and dopamine. Release of the hormones epinephrine and norepinephrine from the adrenal medulla of the adrenal glands is part of the fight-or-flight response. Tyrosine is created from phenylalanine by hydroxylation by the enzyme phenylalanine hydroxylase. Tyrosine is also ingested directly from dietary prote ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alpha Blocker
Alpha blockers, also known as α-blockers or α-adrenoreceptor antagonists, are a class of pharmacological agents that act as antagonists on α-adrenergic receptors ( α-adrenoceptors). Historically, alpha-blockers were used as a tool for pharmacologic research to develop a greater understanding of the autonomic nervous system. Using alpha blockers, scientists began characterizing arterial blood pressure and central vasomotor control in the autonomic nervous system. Today, they can be used as clinical treatments for a limited number of diseases. Alpha blockers can treat a small range of diseases such as hypertension, Raynaud's disease, benign prostatic hyperplasia (BPH) and erectile dysfunction. Generally speaking, these treatments function by binding an α-blocker to α receptors in the arteries and smooth muscle. Ultimately, depending on the type of alpha receptor, this relaxes the smooth muscle or blood vessels, which increases fluid flow in these entities. Classificat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PET Scan
Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in Metabolism, metabolic processes, and in other physiological activities including blood flow, regional chemical composition, and absorption. Different tracers are used for various imaging purposes, depending on the target process within the body, such as: * Fluorodeoxyglucose (18F), Fluorodeoxyglucose ([18F]FDG or FDG) is commonly used to detect cancer; * Sodium fluoride#Medical imaging, [18F]Sodium fluoride (Na18F) is widely used for detecting bone formation; * Oxygen-15 (15O) is sometimes used to measure blood flow. PET is a common medical imaging, imaging technique, a Scintigraphy#Process, medical scintillography technique used in nuclear medicine. A radiopharmaceutical—a radioisotope attached to a drug—is injected into the body as a radioactive tracer, tracer. When the radiopharmaceutical undergoes beta plus decay ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doxazosin
Doxazosin, sold under the brand name Cardura among others, is a medication used to treat symptoms of benign prostatic hyperplasia (enlarged prostate), hypertension (high blood pressure), and post-traumatic stress disorder (PTSD). For high blood pressure, it is a less preferred option. It is taken by mouth. Common side effects include dizziness, sleepiness, swelling, nausea, shortness of breath, and abdominal pain. Severe side effects may include low blood pressure with standing, an irregular heart beat, and priapism. It is a selective Alpha-1 blocker, α1-adrenergic blocker in the quinazoline class of compounds. Doxazosin was patented in 1977 and came into medical use in 1988. It is available as a generic medication. In 2022, it was the 180th most commonly prescribed medication in the United States, with more than 2million prescriptions. Medical uses High blood pressure Doxazosin is usually added to other antihypertensive therapy such as calcium channel antagonists, diureti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypertension
Hypertension, also known as high blood pressure, is a Chronic condition, long-term Disease, medical condition in which the blood pressure in the artery, arteries is persistently elevated. High blood pressure usually does not cause symptoms itself. It is, however, a major risk factor for stroke, coronary artery disease, heart failure, atrial fibrillation, peripheral arterial disease, vision loss, chronic kidney disease, and dementia. Hypertension is a major cause of premature death worldwide. High blood pressure is classified as essential hypertension, primary (essential) hypertension or secondary hypertension. About 90–95% of cases are primary, defined as high blood pressure due to non-specific lifestyle and Genetics, genetic factors. Lifestyle factors that increase the risk include excess salt in the diet, overweight, excess body weight, smoking, physical inactivity and Alcohol (drug), alcohol use. The remaining 5–10% of cases are categorized as secondary hypertension, d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypertensive Crisis
Severely elevated blood pressure (equal to or greater than 180 mmHg systolic or 120 mmHg diastolic) is referred to as a hypertensive crisis (sometimes termed malignant or accelerated hypertension), due to the high risk of complications. People with blood pressures in this range may have no symptoms, but are more likely to report headaches (22% of cases) and dizziness than the general population. Other symptoms accompanying a hypertensive crisis may include visual deterioration due to retinopathy, breathlessness due to heart failure, or a general feeling of malaise due to kidney failure. Most people with a hypertensive crisis are known to have elevated blood pressure, but additional triggers may have led to a sudden rise. Symptoms and treatment A " hypertensive emergency" is diagnosed when there is evidence of direct damage to one or more organs as a result of severely elevated blood pressure greater than 180 mmHg systolic or 120 mmHg diastolic. This may include hypertensiv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
