The cells of the body which stain with chromium salts. They occur along the sympathetic nerves, in the adrenal gland, and in various other organs.
Cells that store epinephrine secretory vesicles. During times of stress, the nervous system signals the vesicles to secrete their hormonal content. Their name derives from their ability to stain a brownish color with chromic salts. Characteristically, they are located in the adrenal medulla and paraganglia (PARAGANGLIA, CHROMAFFIN) of the sympathetic nervous system.
Organelles in CHROMAFFIN CELLS located in the adrenal glands and various other organs. These granules are the site of the synthesis, storage, metabolism, and secretion of EPINEPHRINE and NOREPINEPHRINE.
The inner portion of the adrenal gland. Derived from ECTODERM, adrenal medulla consists mainly of CHROMAFFIN CELLS that produces and stores a number of NEUROTRANSMITTERS, mainly adrenaline (EPINEPHRINE) and NOREPINEPHRINE. The activity of the adrenal medulla is regulated by the SYMPATHETIC NERVOUS SYSTEM.
A general class of ortho-dihydroxyphenylalkylamines derived from tyrosine.
A pair of glands located at the cranial pole of each of the two KIDNEYS. Each adrenal gland is composed of two distinct endocrine tissues with separate embryonic origins, the ADRENAL CORTEX producing STEROIDS and the ADRENAL MEDULLA producing NEUROTRANSMITTERS.
Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.
Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.
A group of acidic proteins that are major components of SECRETORY GRANULES in the endocrine and neuroendocrine cells. They play important roles in the aggregation, packaging, sorting, and processing of secretory protein prior to secretion. They are cleaved to release biologically active peptides. There are various types of granins, usually classified by their sources.
A type of chromogranin which was first isolated from CHROMAFFIN CELLS of the ADRENAL MEDULLA but is also found in other tissues and in many species including human, bovine, rat, mouse, and others. It is an acidic protein with 431 to 445 amino acid residues. It contains fragments that inhibit vasoconstriction or release of hormones and neurotransmitter, while other fragments exert antimicrobial actions.
Dopamine beta-Hydroxylase is an enzyme that catalyzes the conversion of dopamine to norepinephrine, a crucial step in the synthesis of catecholamines within the adrenal glands and central nervous system.
A methyltransferase that catalyzes the reaction of S-adenosyl-L-methionine and phenylethanolamine to yield S-adenosyl-L-homocysteine and N-methylphenylethanolamine. It can act on various phenylethanolamines and converts norepinephrine into epinephrine. (From Enzyme Nomenclature, 1992) EC
A benzoate-cevane found in VERATRUM and Schoenocaulon. It activates SODIUM CHANNELS to stay open longer than normal.
A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.
Vesicles derived from the GOLGI APPARATUS containing material to be released at the cell surface.
A glycoside obtained from Digitalis purpurea; the aglycone is digitogenin which is bound to five sugars. Digitonin solubilizes lipids, especially in membranes and is used as a tool in cellular biochemistry, and reagent for precipitating cholesterol. It has no cardiac effects.
Small masses of chromaffin cells found near the SYMPATHETIC GANGLIA along the ABDOMINAL AORTA, beginning cranial to the superior mesenteric artery (MESENTERIC ARTERY, SUPERIOR) or renal arteries and extending to the level of the aortic bifurcation or just beyond. They are also called the organs of Zuckerkandl and sometimes called aortic bodies (not to be confused with AORTIC BODIES in the THORAX). The para-aortic bodies are the dominant source of CATECHOLAMINES in the FETUS and normally regress after BIRTH.
Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.
A selective nicotinic cholinergic agonist used as a research tool. DMPP activates nicotinic receptors in autonomic ganglia but has little effect at the neuromuscular junction.
Nicotine is highly toxic alkaloid. It is the prototypical agonist at nicotinic cholinergic receptors where it dramatically stimulates neurons and ultimately blocks synaptic transmission. Nicotine is also important medically because of its presence in tobacco smoke.
One of the endogenous pentapeptides with morphine-like activity. It differs from LEU-ENKEPHALIN by the amino acid METHIONINE in position 5. Its first four amino acid sequence is identical to the tetrapeptide sequence at the N-terminal of BETA-ENDORPHIN.
Precursor of epinephrine that is secreted by the adrenal medulla and is a widespread central and autonomic neurotransmitter. Norepinephrine is the principal transmitter of most postganglionic sympathetic fibers and of the diffuse projection system in the brain arising from the locus ceruleus. It is also found in plants and is used pharmacologically as a sympathomimetic.
An enzyme that catalyzes the conversion of L-tyrosine, tetrahydrobiopterin, and oxygen to 3,4-dihydroxy-L-phenylalanine, dihydrobiopterin, and water. EC
The active sympathomimetic hormone from the ADRENAL MEDULLA. It stimulates both the alpha- and beta- adrenergic systems, causes systemic VASOCONSTRICTION and gastrointestinal relaxation, stimulates the HEART, and dilates BRONCHI and cerebral vessels. It is used in ASTHMA and CARDIAC FAILURE and to delay absorption of local ANESTHETICS.
A toxic alkaloid found in Amanita muscaria (fly fungus) and other fungi of the Inocybe species. It is the first parasympathomimetic substance ever studied and causes profound parasympathetic activation that may end in convulsions and death. The specific antidote is atropine.
Condensed areas of cellular material that may be bounded by a membrane.
A type of chromogranin which was initially characterized in a rat PHEOCHROMOCYTOMA CELL LINE. It is found in many species including human, rat, mouse, and others. It is an acidic protein with 626 to 657 amino acid residues. In some species, it inhibits secretion of PARATHYROID HORMONE or INSULIN and exerts bacteriolytic effects in others.
One of the three major families of endogenous opioid peptides. The enkephalins are pentapeptides that are widespread in the central and peripheral nervous systems and in the adrenal medulla.
A subtype of enteroendocrine cells found in the gastrointestinal MUCOSA, particularly in the glands of PYLORIC ANTRUM; DUODENUM; and ILEUM. These cells secrete mainly SEROTONIN and some neuropeptides. Their secretory granules stain readily with silver (argentaffin stain).
Small bodies containing chromaffin cells occurring outside of the adrenal medulla, most commonly near the sympathetic ganglia and in organs such as the kidney, liver, heart and gonads.
A usually benign, well-encapsulated, lobular, vascular tumor of chromaffin tissue of the ADRENAL MEDULLA or sympathetic paraganglia. The cardinal symptom, reflecting the increased secretion of EPINEPHRINE and NOREPINEPHRINE, is HYPERTENSION, which may be persistent or intermittent. During severe attacks, there may be HEADACHE; SWEATING, palpitation, apprehension, TREMOR; PALLOR or FLUSHING of the face, NAUSEA and VOMITING, pain in the CHEST and ABDOMEN, and paresthesias of the extremities. The incidence of malignancy is as low as 5% but the pathologic distinction between benign and malignant pheochromocytomas is not clear. (Dorland, 27th ed; DeVita Jr et al., Cancer: Principles & Practice of Oncology, 3d ed, p1298)
Thin structures that encapsulate subcellular structures or ORGANELLES in EUKARYOTIC CELLS. They include a variety of membranes associated with the CELL NUCLEUS; the MITOCHONDRIA; the GOLGI APPARATUS; the ENDOPLASMIC RETICULUM; LYSOSOMES; PLASTIDS; and VACUOLES.
An annexin family member that plays a role in MEMBRANE FUSION and signaling via VOLTAGE-DEPENDENT CALCIUM CHANNELS.
A drug formerly used as an antipsychotic and treatment of various movement disorders. Tetrabenazine blocks neurotransmitter uptake into adrenergic storage vesicles and has been used as a high affinity label for the vesicle transport system.
The rate dynamics in chemical or physical systems.
An alkaloid found in the roots of Rauwolfia serpentina and R. vomitoria. Reserpine inhibits the uptake of norepinephrine into storage vesicles resulting in depletion of catecholamines and serotonin from central and peripheral axon terminals. It has been used as an antihypertensive and an antipsychotic as well as a research tool, but its adverse effects limit its clinical use.
A CELL LINE derived from a PHEOCHROMOCYTOMA of the rat ADRENAL MEDULLA. PC12 cells stop dividing and undergo terminal differentiation when treated with NERVE GROWTH FACTOR, making the line a useful model system for NERVE CELL differentiation.
The ability of a substrate to retain an electrical charge.

Action potentials in the rat chromaffin cell and effects of acetylcholine. (1/442)

1. Electrophysiological properties of the rat chromaffin cell were studied using intracellular recording techniques. 2. The resting potential in the chromaffin cell was -49 +/- 6 mV (mean +/- S.D., n = 14) in standard saline containing 10 mM-Ca whereas that in Na-free saline was -63 +/- 9 mV (n = 17). At rest, the membrane has a substantial Na permeability. 3. Action potentials were evoked by passing current through the recording electrode. In standard saline the major fraction of the action potential disappeared either upon omission of external Na ions from standard saline or addition of 1 muM tetrodotoxin (TTX). We conclude that action potentials in the chromaffin cell are due mainly to an increase in the permeability of the membrane to Na ions. 4. Small but significant regenerative action potentials were observed in Na-free saline, and when Ca in Na-free saline was replaced by Ba, prolonged action potentials occurred. We conclude that action potentials in the chromaffin cell also have a Ca component. 5. Iontophoretic application of acetylcholine (ACh) produced a transient membrane depolarization in standard saline. 6. Spontaneous action potentials were recorded extracellularly by microsuction electrodes. They occurred at a rate of 0-05-0-1/sec in almost all cells. 7. When the perfusion fluid contained 3 x 10(-7) M to 10(-4) M ACh the spike frequency increased up to about 2/sec. This stimulatory effect of ACh was blocked by 10(-7) M atropine but not by 10(-3) M hexamethonium nor by 10(-5) M-d-tubocurarine. 8. The importance of Ca entry during action potentials for catecholamine secretion is discussed  (+info)

Modulation of gastrin processing by vesicular monoamine transporter type 1 (VMAT1) in rat gastrin cells. (2/442)

1. Gastrointestinal endocrine cells produce biogenic amines which are transported into secretory vesicles by one of two proton-amine exchangers, vesicular monoamine transporters type 1 and 2 (VMAT1 and 2). We report here the presence of VMAT1 in rat gastrin (G) cells and the relevance of VMAT1 function for the modulation of progastrin processing by biogenic and dietary amines. 2. In immunocytochemical studies VMAT1, but not VMAT2, was localized to subpopulations of G cells and enterochromaffin (EC) cells; neither was found in antral D cells. The expression of VMAT1 in antral mucosa was confirmed by Northern blot analysis, which revealed an mRNA band of approximately 3.2 kb, and by Western blot analysis, which revealed a major protein of 55 kDa. 3. In pulse-chase labelling experiments, the conversion of the amidated gastrin G34 to G17 was inhibited by biogenic amine precursors (L-DOPA and 5-hydroxytryptophan). This inhibition was stereospecific and sensitive to reserpine (50 nM), which blocks VMAT1 and VMAT2, but resistant to tetrabenazine, which is a selective inhibitor of VMAT2. 4. Dietary amines such as tyramine and tryptamine also inhibited G34 cleavage. This effect was associated with a loss of the electron-dense core of G cell secretory vesicles. It was not stereospecific or reserpine sensitive, but was correlated with hydrophobicity. 5. Thus rat antral G cells can express VMAT1; transport of biogenic amines into secretory vesicles by VMAT1 is associated with inhibition of G34 cleavage, perhaps by raising intravesicular pH. Dietary amines also modulate cleavage of progastrin-derived peptides, but do so by a VMAT1-independent mechanism; they may act as weak bases that passively permeate secretory vesicle membranes and raise intravesicular pH.  (+info)

Subcellualr distribution of protein carboxymethylase and its endogenous substrates in the adrenal medulla: possible role in excitation-secretion coupling. (3/442)

Protein carboxymethylase (S-adenosyl-L-methionine:protein O-methyltransferase, EC transfers a methyl group from S-adenoxyl-L-methionine to carboxyl side chains of proteins to form labile protein-methyl esters which, thus, neutralize negative charges. This enzyme was examined for its possible participation in excitation-secretion coupling in the adrenal medulla. Protein carboxymethylase has a specific activity several times higher in the adrenal medulla than in the adrenal cortex; also, the medulla has a higher concentration of methyl-acceptor proteins. In the adrenal medulla, 97% of the enzyme was localized in the cytosol. Of the various subcellular fractions of the medulla, the catecholamine-containing chromaffin vesicles had the highest concentrations of substrat(s) for protein carboxymethylase. Carboxymethylation of proteins in intact chromaffin vesicles results in stripping of methylated protein(s) from the membranes. Thus, protein carboxymethylase appears to be involved in the neutralization of charges on the surface of chromaffin vesicles and in the release of surface proteins; both phenomena are likely to be required for exocytosis.  (+info)

Desensitisation of chromaffin cell nicotinic receptors does not impede catecholamine secretion during acute hypoxia in rainbow trout (Oncorhynchus mykiss). (4/442)

Experiments were performed on adult rainbow trout (Oncorhynchus mykiss) in vivo using chronically cannulated fish and in situ using a perfused posterior cardinal vein preparation (i) to characterise the desensitisation of chromaffin cell nicotinic receptors and (ii) to assess the ability of fish to secrete catecholamines during acute hypoxia with or without functional nicotinic receptors. Intra-arterial injection of nicotine (6.0x10(-)(7 )mol kg(-)(1)) caused a rapid increase in plasma adrenaline and noradrenaline levels; the magnitude of this response was unaffected by an injection of nicotine given 60 min earlier. Evidence for nicotinic receptor desensitisation, however, was provided during continuous intravenous infusion of nicotine (1.3x10(-)(5 )mol kg(-)(1 )h(-)(1)) in which plasma catecholamine levels increased initially but then returned to baseline levels. To ensure that the decline in circulating catecholamine concentrations during continuous nicotine infusion was not related to changes in storage levels or altered rates of degradation/clearance, in situ posterior cardinal vein preparations were derived from fish previously experiencing 60 min of saline or nicotine infusion. Confirmation of nicotinic receptor desensitisation was provided by demonstrating that the preparations derived from nicotine-infused fish were unresponsive to nicotine (10(-)(5 )mol l(-)(1)), yet remained responsive to angiotensin II (500 pmol kg(-)(1)). The in situ experiments demonstrated that desensitisation of the nicotinic receptor occurred within 5 min of receptor stimulation and that resensitisation was established 40 min later. The ability to elevate plasma catecholamine levels during acute hypoxia (40-45 mmHg; 5.3-6.0 kPa) was not impaired in fish experiencing nicotinic receptor desensitisation. Indeed, peak plasma adrenaline levels were significantly higher in the desensitised fish during hypoxia than in controls (263+/-86 versus 69+/-26 nmol l(-)(1); means +/- s.e.m., N=6-9). Thus, the results of the present study demonstrate that activation of preganglionic sympathetic cholinergic nerve fibres and the resultant stimulation of nicotinic receptors is not the sole mechanism for eliciting catecholamine secretion during hypoxia.  (+info)

Tumours of the adrenal gland and paraganglia. (5/442)

This classification is arranged in two parts in order to take into account the different origins, structures, and functions of the cortex and medulla. The tabular classification is a simplified version of that suggested for adrenal tumours in man, and includes cortical adenoma and carcinoma, phaeochromocytoma, chemodectoma, neurofibroma, ganglioneuroma and ganglioneuroblastoma, and neuroblastoma. A detailed functional classification is not given, since the hormonal activity of many adrenal tumours in animals is less well known than it is in man. Of the tumour-like lesions listed, cortical hyperplasia is particularly important in several species.  (+info)

Ion permeability of isolated chromaffin granules. (6/442)

The passive ion permeability, regulation of volume, and internal pH of isolated bovine chromaffin granules were studied by radiochemical, potentiometric, gravimetric, and spectrophotometric techniques. Chromaffin granules behave as perfect osmometers between 340 and 1,000 mosM in choline chloride, NaCl, and KCl as measured by changes in absorbance at 430 nm or from intragranular water measurements using 3H2O and [14C]polydextran. By suspending chromaffin granules in iso-osmotic media of various metal ions and selectively increasing the permeability to either the cation or the anion by intrinsically permeable ions or specific ionophores, it was possible to determine by turbidity and potentiometric measurements the permeability to the counterion. These measurements indicate that the chromaffin granule is impermeable to the cations tested (Na+, K+, and H+). Limited H+ permeability across the chromaffin granule membrane was also shown by means of the time course of pH re-equilibration after pulsed pH changes in the surrounding media. The measurement of [14C]methylamine distribution indicates that a significant deltapH exists across the membrane, inside acidic, which at an external value of 6.85 has a value of 1.16. The deltapH is relatively insensitive to changes in the composition of the external media and can be enhanced or collapsed by the addition of ionophores and uncouplers. Measurement at various values of external pH indicates an internal pH of 5.5. Use of the ionophore A23187 indicates that Ca++ and Mg++ can be accumulated against an apparent concentration gradient with calcium uptake exceeding 50 nmol/mg of protein at saturation. These measurements also show that Ca++ and Mg++ are impermeable. Measurement of catecholamine release under conditions where intravesicular calcium accumulation is maximal indicates that catecholamine release does not occur. The physiological significance of the high impermeability to ions and the existence of a large deltapH are discussed in terms of regulation of uptake, storage, and release of catecholamines in chromaffin granules.  (+info)

Release of catecholamines and dopamine beta-hydroxylase from the perfused adrenal gland of the cat. (7/442)

1. Secretion of catecholamines (CA) and dopamine beta-hydroxylase (DBH) activity from the perfused cat adrenal gland was studied following splanchnic nerve stimulation or infusion of acetylcholine (ACh). 2. Splanchnic nerve stimulation (30 Hz) or perfusion with a low concentration of ACh (10-minus5 M) caused a marked release of CA in the venous effluent, but release of DBH activity was minimal while a higher concentration of ACh (10-minus 4 M) enhanced the release of CA and DBH. 3. The ratio of DBH/CA released in the perfusate by splanchnic nerve stimulation or ACh infusion was only a small fraction of the ratio in the soluble lysate of purified chromaffin vesicles. 4. Following reserpine treatment, adrenal CA levels fell to 25% of the control value in 24 hr, remained depressed on days 2, 3, 4 and 5 at 5% of the control and recovered to 60% of the control value on the 6th day. DBH activity was unchanged from the control value at 24 hr after treatment, then rose as high as 5 times the control on the 5th day and was still twice the control value on the 6th day. 5. CA secretion in response to ACh (10-minus 4 M) perfusion was reduced to 30% of the control value on the first day after reserpine treatment, while DBH secretion was unchanged. On the 2nd day, CA secretion was depressed further to 5% of the control and remained at this low level up to 5 days after treatment while DBH secretion was twice the control value at 48 hr and then on days 3, 4 and 5 rose up to 5 times the control value. On the 6th day, secretion of CA recovered to 30% of the control while DBH secretion was now twice the control. 6. Isopycnic sucrose density (discontinuous) gradient centrifugation of vesicles from adrenal glands of control cats, and of cats given reserpine 1 or 2 days perviously, indicated that new vesicles or vesicles depleted of CA by reserpine had a lower equilibrium density than the original population of vesicles. 7. These results suggest that the release of CA is quantal in nature, but the release of DBH is not necessarily coupled with it. Release of DBH by ACh from reserpinized glands suggests that the vesicles which were once involved in secretion may be re-used for synthesis and storage of CA.  (+info)

Discrimination of monoamine uptake by membranes of adrenal chromaffin granules. (8/442)

1 The accumulation of various radioactive monoamines by isolated membranes of bovine adrenal chromaffin granules was measured by equilibrium dialysis. 2 Adenosine-5'-triphosphate (ATP) in the presence of Mg++ stimulated the uptake of all the amines tested, but the accumulation of dopamine, (-)-noradrenaline (NA), 5-hydroxytryptamine (5-HT), (plus or minus)-adrenaline and (plus or minus)-octopamine was greater than that of tyramine, (plus or minus)-metaraminol, tryptamine, beta-phenylethylamine and histamine. 3 At the higher concentration levels of the amines in the medium the ATP-dependent accumulation of dopamine, NA, adrenaline and 5-HT in the membranes reached a saturation level, whereas in the absence of the nucleotide no saturation level was attained. 4 Octopamine and 5-HT competitively inhibited the ATP-dependent uptake of NA, 5 Decrease in the incubation temperature or the presence of N-ethylameimide greatly reduced the ATP-stimulated amine accumulation. Ouabain had no effect on uptake. 6 Reserpine virtually abolished the ATP-dependent uptake of dopamine, NA and 5-HT, caused a partial inhibition of the metaraminol, octopamine and tyramine accumulation, but did not interfere with the uptake of tryptamine. 7 The content of endogenous catecholamines of the membranes was changed very little by incubation of NA and 5-HT in the presence of ATP. However, the membranes lost over 80% of their endogenous amines if incubated for 30 min without ATP. 8 The ATP content of the medium progressively decreased during the incubation of granular membranes. 9 It is concluded that the membrane of adrenal chromaffin granules discriminates between the various monoamines with regard to the magnitude of their uptake and that two mechanisms of ATP-stimulated uptake, one responsive and the other resistant to reserpine, exist at the level of this membrane. The ATP-stimulated transport at the granular membrane level may be an important factor in determining the intraneuronal storage of a physiological or false neurotransmitter.  (+info)

The chromaffin system is a part of the autonomic nervous system that consists of specialized cells called chromaffin cells. These cells are found in two main locations: the adrenal medulla, which is the inner portion of the adrenal glands located on top of the kidneys; and scattered throughout various nerve ganglia along the sympathetic trunk, a chain of ganglia that runs parallel to the spinal cord.

Chromaffin cells are responsible for synthesizing, storing, and releasing catecholamines, which are hormones and neurotransmitters that help regulate various bodily functions such as heart rate, blood pressure, and metabolism. The most well-known catecholamines are adrenaline (epinephrine) and noradrenaline (norepinephrine), which are released in response to stress or excitement.

The term "chromaffin" refers to the ability of these cells to take up chromium salts and produce a brown coloration, which is why they are called chromaffin cells. The chromaffin system plays an important role in the body's fight-or-flight response, helping to prepare the body for immediate action in response to perceived threats or stressors.

Chromaffin cells are specialized neuroendocrine cells that are responsible for the synthesis and release of catecholamines, which are hormones such as adrenaline (epinephrine) and noradrenaline (norepinephrine). These cells are located in the medulla of the adrenal gland and in some autonomic ganglia outside the central nervous system. Chromaffin cells contain secretory granules that stain brown with chromium salts, hence their name. They play a crucial role in the body's response to stress by releasing catecholamines into the bloodstream, which helps prepare the body for the "fight or flight" response.

Chromaffin granules are membrane-bound organelles found in the cytoplasm of chromaffin cells, which are a type of neuroendocrine cell. These cells are located in the adrenal medulla and some sympathetic ganglia and play a crucial role in the body's stress response.

Chromaffin granules contain a variety of substances, including catecholamines such as epinephrine (adrenaline) and norepinephrine (noradrenaline), as well as proteins and other molecules. When the chromaffin cell is stimulated, the granules fuse with the cell membrane and release their contents into the extracellular space, where they can bind to receptors on nearby cells and trigger a variety of physiological responses.

The name "chromaffin" comes from the fact that these granules contain enzymes that can react with chromium salts to produce a brown color, which is why they are also sometimes referred to as "black-brown granules."

The adrenal medulla is the inner part of the adrenal gland, which is located on top of the kidneys. It is responsible for producing and releasing hormones such as epinephrine (also known as adrenaline) and norepinephrine (also known as noradrenaline). These hormones play a crucial role in the body's "fight or flight" response, preparing the body for immediate action in response to stress.

Epinephrine increases heart rate, blood pressure, and respiratory rate, while also increasing blood flow to muscles and decreasing blood flow to the skin and digestive system. Norepinephrine has similar effects but is generally less potent than epinephrine. Together, these hormones help to prepare the body for physical activity and increase alertness and focus.

Disorders of the adrenal medulla can lead to a variety of symptoms, including high blood pressure, rapid heart rate, anxiety, and tremors. Some conditions that affect the adrenal medulla include pheochromocytoma, a tumor that causes excessive production of epinephrine and norepinephrine, and neuroblastoma, a cancerous tumor that arises from immature nerve cells in the adrenal gland.

Catecholamines are a group of hormones and neurotransmitters that are derived from the amino acid tyrosine. The most well-known catecholamines are dopamine, norepinephrine (also known as noradrenaline), and epinephrine (also known as adrenaline). These hormones are produced by the adrenal glands and are released into the bloodstream in response to stress. They play important roles in the "fight or flight" response, increasing heart rate, blood pressure, and alertness. In addition to their role as hormones, catecholamines also function as neurotransmitters, transmitting signals in the nervous system. Disorders of catecholamine regulation can lead to a variety of medical conditions, including hypertension, mood disorders, and neurological disorders.

The adrenal glands are a pair of endocrine glands that are located on top of the kidneys. Each gland has two parts: the outer cortex and the inner medulla. The adrenal cortex produces hormones such as cortisol, aldosterone, and androgens, which regulate metabolism, blood pressure, and other vital functions. The adrenal medulla produces catecholamines, including epinephrine (adrenaline) and norepinephrine (noradrenaline), which help the body respond to stress by increasing heart rate, blood pressure, and alertness.

"Cattle" is a term used in the agricultural and veterinary fields to refer to domesticated animals of the genus *Bos*, primarily *Bos taurus* (European cattle) and *Bos indicus* (Zebu). These animals are often raised for meat, milk, leather, and labor. They are also known as bovines or cows (for females), bulls (intact males), and steers/bullocks (castrated males). However, in a strict medical definition, "cattle" does not apply to humans or other animals.

Exocytosis is the process by which cells release molecules, such as hormones or neurotransmitters, to the extracellular space. This process involves the transport of these molecules inside vesicles (membrane-bound sacs) to the cell membrane, where they fuse and release their contents to the outside of the cell. It is a crucial mechanism for intercellular communication and the regulation of various physiological processes in the body.

Chromogranins are a group of proteins that are stored in the secretory vesicles of neuroendocrine cells, including neurons and endocrine cells. These proteins are co-released with neurotransmitters and hormones upon stimulation of the cells. Chromogranin A is the most abundant and best studied member of this protein family.

Chromogranins have several functions in the body. They play a role in the biogenesis, processing, and storage of neuropeptides and neurotransmitters within secretory vesicles. Additionally, chromogranins can be cleaved into smaller peptides, some of which have hormonal or regulatory activities. For example, vasostatin-1, a peptide derived from chromogranin A, has been shown to have vasodilatory and cardioprotective effects.

Measurement of chromogranin levels in blood can be used as a biomarker for the diagnosis and monitoring of neuroendocrine tumors, which are characterized by excessive secretion of chromogranins and other neuroendocrine markers.

Chromogranin A is a protein that is widely used as a marker for neuroendocrine tumors. These are tumors that arise from cells of the neuroendocrine system, which is a network of cells throughout the body that produce hormones and help to regulate various bodily functions. Chromogranin A is stored in secretory granules within these cells and is released into the bloodstream when the cells are stimulated to release their hormones.

Chromogranin A is measured in the blood as a way to help diagnose neuroendocrine tumors, monitor the effectiveness of treatment, and track the progression of the disease. Elevated levels of chromogranin A in the blood may indicate the presence of a neuroendocrine tumor, although other factors can also cause an increase in this protein.

It's important to note that while chromogranin A is a useful marker for neuroendocrine tumors, it is not specific to any one type of tumor and should be used in conjunction with other diagnostic tests and clinical evaluation.

Dopamine beta-hydroxylase (DBH) is an enzyme that plays a crucial role in the synthesis of catecholamines, which are important neurotransmitters and hormones in the human body. Specifically, DBH converts dopamine into norepinephrine, another essential catecholamine.

DBH is primarily located in the adrenal glands and nerve endings of the sympathetic nervous system. It requires molecular oxygen, copper ions, and vitamin C (ascorbic acid) as cofactors to perform its enzymatic function. Deficiency or dysfunction of DBH can lead to various medical conditions, such as orthostatic hypotension and neuropsychiatric disorders.

Phenylethanolamine N-Methyltransferase (PNMT) is a enzyme that plays a crucial role in the synthesis of epinephrine (also known as adrenaline). It catalyzes the transfer of a methyl group from S-adenosylmethionine to the nitrogen atom of the amine group of normetanephrine, resulting in the formation of epinephrine.

PNMT is primarily found in the chromaffin cells of the adrenal medulla, where it is responsible for the final step in the biosynthesis of epinephrine. The activity of PNMT is regulated by several factors, including glucocorticoids, which increase its expression and activity, leading to an elevation in epinephrine levels.

Epinephrine is a hormone and neurotransmitter that plays a critical role in the body's response to stress, preparing it for the "fight or flight" response by increasing heart rate, blood pressure, and respiration, among other effects.

Veratridine is not a medical term, but it is a chemical compound that has been used in scientific research. It's a plant alkaloid found primarily in the seeds and roots of various Veratrum species (also known as false hellebore or white hellebore).

In a pharmacological context, veratridine can be defined as:

A steroidal alkaloid that acts as a potent agonist at voltage-gated sodium channels in excitable membranes. It causes persistent activation of these channels, leading to sustained depolarization and increased neuronal excitability. Veratridine has been used in research to study the properties and functions of sodium channels, as well as neurotransmission and nerve impulse transmission.

However, it is not a term typically used in clinical medicine or patient care.

Calcium is an essential mineral that is vital for various physiological processes in the human body. The medical definition of calcium is as follows:

Calcium (Ca2+) is a crucial cation and the most abundant mineral in the human body, with approximately 99% of it found in bones and teeth. It plays a vital role in maintaining structural integrity, nerve impulse transmission, muscle contraction, hormonal secretion, blood coagulation, and enzyme activation.

Calcium homeostasis is tightly regulated through the interplay of several hormones, including parathyroid hormone (PTH), calcitonin, and vitamin D. Dietary calcium intake, absorption, and excretion are also critical factors in maintaining optimal calcium levels in the body.

Hypocalcemia refers to low serum calcium levels, while hypercalcemia indicates high serum calcium levels. Both conditions can have detrimental effects on various organ systems and require medical intervention to correct.

Secretory vesicles are membrane-bound organelles found within cells that store and transport secretory proteins and other molecules to the plasma membrane for exocytosis. Exocytosis is the process by which these molecules are released from the cell, allowing them to perform various functions, such as communication with other cells or participation in biochemical reactions. Secretory vesicles can be found in a variety of cell types, including endocrine cells, exocrine cells, and neurons. The proteins and molecules contained within secretory vesicles are synthesized in the rough endoplasmic reticulum and then transported to the Golgi apparatus, where they are processed, modified, and packaged into the vesicles for subsequent release.

Digitonin is a type of saponin, which is a natural substance found in some plants. It is often used in laboratory settings as a detergent to disrupt cell membranes and make it easier to study the contents of cells. Digitonin specifically binds to cholesterol in cell membranes, making it a useful tool for studying cholesterol-rich structures such as lipid rafts. It is not used as a medication in humans.

Para-aortic bodies, also known as autonomic ganglia or para-aortic chains, are clusters of nerve cells (ganglia) located near the aorta, the largest artery in the body. These ganglia are part of the autonomic nervous system, which controls involuntary bodily functions such as heart rate, digestion, and respiratory rate.

The para-aortic bodies are primarily responsible for regulating the function of the organs in the abdomen and pelvis. They receive input from sensory neurons and send output to effector organs through a complex network of nerves. The neurotransmitters acetylcholine and noradrenaline are released at these ganglia to mediate the transmission of signals between nerve cells.

These structures can be important in the diagnosis and treatment of certain medical conditions, such as neuroblastoma, a type of cancer that arises from immature nerve cells in infants and children. In some cases, surgical removal of para-aortic bodies may be necessary to treat this condition.

"Cells, cultured" is a medical term that refers to cells that have been removed from an organism and grown in controlled laboratory conditions outside of the body. This process is called cell culture and it allows scientists to study cells in a more controlled and accessible environment than they would have inside the body. Cultured cells can be derived from a variety of sources, including tissues, organs, or fluids from humans, animals, or cell lines that have been previously established in the laboratory.

Cell culture involves several steps, including isolation of the cells from the tissue, purification and characterization of the cells, and maintenance of the cells in appropriate growth conditions. The cells are typically grown in specialized media that contain nutrients, growth factors, and other components necessary for their survival and proliferation. Cultured cells can be used for a variety of purposes, including basic research, drug development and testing, and production of biological products such as vaccines and gene therapies.

It is important to note that cultured cells may behave differently than they do in the body, and results obtained from cell culture studies may not always translate directly to human physiology or disease. Therefore, it is essential to validate findings from cell culture experiments using additional models and ultimately in clinical trials involving human subjects.

Dimethylphenylpiperazinium iodide is not a medical term or a medication commonly used in clinical practice. It's a chemical compound with the formula (C12H18N2)I, where dimethylphenylpiperazinium is the cation and iodide is the anion.

The dimethylphenylpiperazinium portion of the molecule consists of a phenyl ring with two methyl groups attached to it and a piperazine ring, which contains two nitrogen atoms. This compound may be used in research settings for various purposes, including as a reagent or an intermediate in chemical synthesis.

As this compound is not a medication, there is no medical definition associated with it. If you have any questions about its use or potential applications, please consult a relevant professional such as a chemist or pharmacologist.

Nicotine is defined as a highly addictive psychoactive alkaloid and stimulant found in the nightshade family of plants, primarily in tobacco leaves. It is the primary component responsible for the addiction to cigarettes and other forms of tobacco. Nicotine can also be produced synthetically.

When nicotine enters the body, it activates the release of several neurotransmitters such as dopamine, norepinephrine, and serotonin, leading to feelings of pleasure, stimulation, and relaxation. However, with regular use, tolerance develops, requiring higher doses to achieve the same effects, which can contribute to the development of nicotine dependence.

Nicotine has both short-term and long-term health effects. Short-term effects include increased heart rate and blood pressure, increased alertness and concentration, and arousal. Long-term use can lead to addiction, lung disease, cardiovascular disease, and reproductive problems. It is important to note that nicotine itself is not the primary cause of many tobacco-related diseases, but rather the result of other harmful chemicals found in tobacco smoke.

Enkephalins are naturally occurring opioid peptides in the body that bind to opiate receptors and help reduce pain and produce a sense of well-being. There are two major types of enkephalins: Leu-enkephalin and Met-enkephalin, which differ by only one amino acid at the N-terminus.

Methionine-enkephalin (Met-enkephalin) is a type of enkephalin that contains methionine as its N-terminal amino acid. Its chemical formula is Tyr-Gly-Gly-Phe-Met, and it is derived from the precursor protein proenkephalin. Met-enkephalin has a shorter half-life than Leu-enkephalin due to its susceptibility to enzymatic degradation by aminopeptidases.

Met-enkephalin plays an essential role in pain modulation, reward processing, and addiction. It is also involved in various physiological functions, including respiration, cardiovascular regulation, and gastrointestinal motility. Dysregulation of enkephalins has been implicated in several pathological conditions, such as chronic pain, drug addiction, and neurodegenerative disorders.

Norepinephrine, also known as noradrenaline, is a neurotransmitter and a hormone that is primarily produced in the adrenal glands and is released into the bloodstream in response to stress or physical activity. It plays a crucial role in the "fight-or-flight" response by preparing the body for action through increasing heart rate, blood pressure, respiratory rate, and glucose availability.

As a neurotransmitter, norepinephrine is involved in regulating various functions of the nervous system, including attention, perception, motivation, and arousal. It also plays a role in modulating pain perception and responding to stressful or emotional situations.

In medical settings, norepinephrine is used as a vasopressor medication to treat hypotension (low blood pressure) that can occur during septic shock, anesthesia, or other critical illnesses. It works by constricting blood vessels and increasing heart rate, which helps to improve blood pressure and perfusion of vital organs.

Tyrosine 3-Monooxygenase (also known as Tyrosinase or Tyrosine hydroxylase) is an enzyme that plays a crucial role in the synthesis of catecholamines, which are neurotransmitters and hormones in the body. This enzyme catalyzes the conversion of the amino acid L-tyrosine to 3,4-dihydroxyphenylalanine (L-DOPA) by adding a hydroxyl group to the 3rd carbon atom of the tyrosine molecule.

The reaction is as follows:

L-Tyrosine + O2 + pterin (co-factor) -> L-DOPA + pterin (oxidized) + H2O

This enzyme requires molecular oxygen and a co-factor such as tetrahydrobiopterin to carry out the reaction. Tyrosine 3-Monooxygenase is found in various tissues, including the brain and adrenal glands, where it helps regulate the production of catecholamines like dopamine, norepinephrine, and epinephrine. Dysregulation of this enzyme has been implicated in several neurological disorders, such as Parkinson's disease.

Epinephrine, also known as adrenaline, is a hormone and a neurotransmitter that is produced in the body. It is released by the adrenal glands in response to stress or excitement, and it prepares the body for the "fight or flight" response. Epinephrine works by binding to specific receptors in the body, which causes a variety of physiological effects, including increased heart rate and blood pressure, improved muscle strength and alertness, and narrowing of the blood vessels in the skin and intestines. It is also used as a medication to treat various medical conditions, such as anaphylaxis (a severe allergic reaction), cardiac arrest, and low blood pressure.

Muscarine is a naturally occurring organic compound that is classified as an alkaloid. It is found in various mushrooms, particularly those in the Amanita genus such as Amanita muscaria (the fly agaric) and Amanita pantherina. Muscarine acts as a parasympathomimetic, which means it can bind to and stimulate the same receptors as the neurotransmitter acetylcholine in the parasympathetic nervous system. This can lead to various effects on the body, including slowed heart rate, increased salivation, constricted pupils, and difficulty breathing. In high doses, muscarine can be toxic and even life-threatening.

Cytoplasmic granules are small, membrane-bound organelles or inclusions found within the cytoplasm of cells. They contain various substances such as proteins, lipids, carbohydrates, and genetic material. Cytoplasmic granules have diverse functions depending on their specific composition and cellular location. Some examples include:

1. Secretory granules: These are found in secretory cells and store hormones, neurotransmitters, or enzymes before they are released by exocytosis.
2. Lysosomes: These are membrane-bound organelles that contain hydrolytic enzymes for intracellular digestion of waste materials, foreign substances, and damaged organelles.
3. Melanosomes: Found in melanocytes, these granules produce and store the pigment melanin, which is responsible for skin, hair, and eye color.
4. Weibel-Palade bodies: These are found in endothelial cells and store von Willebrand factor and P-selectin, which play roles in hemostasis and inflammation.
5. Peroxisomes: These are single-membrane organelles that contain enzymes for various metabolic processes, such as β-oxidation of fatty acids and detoxification of harmful substances.
6. Lipid bodies (also called lipid droplets): These are cytoplasmic granules that store neutral lipids, such as triglycerides and cholesteryl esters. They play a role in energy metabolism and intracellular signaling.
7. Glycogen granules: These are cytoplasmic inclusions that store glycogen, a polysaccharide used for energy storage in animals.
8. Protein bodies: Found in plants, these granules store excess proteins and help regulate protein homeostasis within the cell.
9. Electron-dense granules: These are found in certain immune cells, such as mast cells and basophils, and release mediators like histamine during an allergic response.
10. Granules of unknown composition or function may also be present in various cell types.

Chromogranin B is a protein that is primarily found in the secretory granules of neuroendocrine cells, including neurons and endocrine cells. These granules are specialized organelles where hormones and neurotransmitters are stored before being released into the extracellular space. Chromogranin B is co-synthesized and packaged with these secretory products and is therefore often used as a marker for neuroendocrine differentiation.

Chromogranin B is a member of the chromogranin/secretogranin family of proteins, which are characterized by their ability to form large aggregates in the acidic environment of secretory granules. These aggregates play a role in the sorting and processing of secretory products, as well as in the regulation of granule biogenesis and exocytosis.

Chromogranin B has been shown to have various biological activities, including inhibition of protein kinase C, stimulation of calmodulin-dependent processes, and modulation of ion channel activity. However, its precise physiological functions remain to be fully elucidated. Dysregulation of chromogranin B expression and processing has been implicated in several pathological conditions, including neurodegenerative diseases and neoplasia.

Enkephalins are naturally occurring opioid peptides that bind to opiate receptors in the brain and other organs, producing pain-relieving and other effects. They are derived from the precursor protein proenkephalin and consist of two main types: Leu-enkephalin and Met-enkephalin. Enkephalins play a role in pain modulation, stress response, mood regulation, and addictive behaviors. They are also involved in the body's reward system and have been implicated in various physiological processes such as respiration, gastrointestinal motility, and hormone release.

Enterochromaffin cells, also known as Kulchitsky cells or enteroendocrine cells, are a type of neuroendocrine cell found in the epithelial lining of the gastrointestinal tract. These cells are responsible for producing and secreting a variety of hormones and neuropeptides that play important roles in regulating gastrointestinal motility, secretion, and sensation.

Enterochromaffin cells are named for their ability to take up chromaffin stains, which contain silver salts and oxidizing agents that react with the catecholamines stored within the cells. These cells can be further classified based on their morphology, location within the gastrointestinal tract, and the types of hormones they produce.

Some examples of hormones produced by enterochromaffin cells include serotonin (5-hydroxytryptamine), histamine, gastrin, somatostatin, and cholecystokinin. Serotonin is one of the most well-known hormones produced by these cells, and it plays a critical role in regulating gastrointestinal motility and secretion, as well as mood and cognition.

Abnormalities in enterochromaffin cell function have been implicated in a number of gastrointestinal disorders, including irritable bowel syndrome (IBS), functional dyspepsia, and gastroparesis. Additionally, mutations in genes associated with enterochromaffin cells have been linked to several inherited cancer syndromes, such as multiple endocrine neoplasia type 1 (MEN1) and neurofibromatosis type 1 (NF1).

Paraganglia, chromaffin are neuroendocrine tissues that are derived from the neural crest and are located outside the adrenal gland. They are capable of producing catecholamines, including epinephrine (adrenaline) and norepinephrine (noradrenaline), in response to various stimuli such as stress or changes in blood pressure.

Chromaffin paraganglia are named for their ability to undergo a chemical reaction that results in brown coloration when exposed to chromium salts, a characteristic known as "chromaffinity." These tissues are found throughout the body, but the majority of them are clustered around the sympathetic and parasympathetic ganglia of the autonomic nervous system.

Examples of chromaffin paraganglia include the adrenal medulla (the inner part of the adrenal gland), the sympathetic paraganglia (such as the organ of Zuckerkandl, which is located near the aorta and is particularly prominent in fetuses and young children), and the parasympathetic paraganglia (such as the carotid body, which is located near the bifurcation of the common carotid artery).

Abnormal growths or tumors of chromaffin paraganglia are called pheochromocytomas if they arise from the adrenal medulla and paragangliomas if they arise from extra-adrenal locations. These tumors can cause excessive production of catecholamines, leading to hypertension, tachycardia, sweating, and other symptoms associated with the "fight or flight" response.

Pheochromocytoma is a rare type of tumor that develops in the adrenal glands, which are triangular-shaped glands located on top of each kidney. These tumors produce excessive amounts of hormones called catecholamines, including adrenaline and noradrenaline. This can lead to a variety of symptoms such as high blood pressure, sweating, headaches, rapid heartbeat, and anxiety.

Pheochromocytomas are typically slow-growing and can be benign or malignant (cancerous). While the exact cause of these tumors is not always known, some genetic factors have been identified that may increase a person's risk. Treatment usually involves surgical removal of the tumor, along with medications to manage symptoms and control blood pressure before and after surgery.

Intracellular membranes refer to the membrane structures that exist within a eukaryotic cell (excluding bacteria and archaea, which are prokaryotic and do not have intracellular membranes). These membranes compartmentalize the cell, creating distinct organelles or functional regions with specific roles in various cellular processes.

Major types of intracellular membranes include:

1. Nuclear membrane (nuclear envelope): A double-membraned structure that surrounds and protects the genetic material within the nucleus. It consists of an outer and inner membrane, perforated by nuclear pores that regulate the transport of molecules between the nucleus and cytoplasm.
2. Endoplasmic reticulum (ER): An extensive network of interconnected tubules and sacs that serve as a major site for protein folding, modification, and lipid synthesis. The ER has two types: rough ER (with ribosomes on its surface) and smooth ER (without ribosomes).
3. Golgi apparatus/Golgi complex: A series of stacked membrane-bound compartments that process, sort, and modify proteins and lipids before they are transported to their final destinations within the cell or secreted out of the cell.
4. Lysosomes: Membrane-bound organelles containing hydrolytic enzymes for breaking down various biomolecules (proteins, carbohydrates, lipids, and nucleic acids) in the process called autophagy or from outside the cell via endocytosis.
5. Peroxisomes: Single-membrane organelles involved in various metabolic processes, such as fatty acid oxidation and detoxification of harmful substances like hydrogen peroxide.
6. Vacuoles: Membrane-bound compartments that store and transport various molecules, including nutrients, waste products, and enzymes. Plant cells have a large central vacuole for maintaining turgor pressure and storing metabolites.
7. Mitochondria: Double-membraned organelles responsible for generating energy (ATP) through oxidative phosphorylation and other metabolic processes, such as the citric acid cycle and fatty acid synthesis.
8. Chloroplasts: Double-membraned organelles found in plant cells that convert light energy into chemical energy during photosynthesis, producing oxygen and organic compounds (glucose) from carbon dioxide and water.
9. Endoplasmic reticulum (ER): A network of interconnected membrane-bound tubules involved in protein folding, modification, and transport; it is divided into two types: rough ER (with ribosomes on the surface) and smooth ER (without ribosomes).
10. Nucleus: Double-membraned organelle containing genetic material (DNA) and associated proteins involved in replication, transcription, RNA processing, and DNA repair. The nuclear membrane separates the nucleoplasm from the cytoplasm and contains nuclear pores for transporting molecules between the two compartments.

Annexin A7 is a type of protein that belongs to the annexin family, which are characterized by their ability to bind to cell membranes in a calcium-dependent manner. Specifically, Annexin A7 (also known as Syntaxin-binding protein 1 or SBP1) is involved in various cellular processes such as exocytosis, endocytosis, and signal transduction. It has been shown to interact with other proteins, including syntaxins, which are important for vesicle trafficking and fusion. Additionally, Annexin A7 may have a role in regulating apoptosis (programmed cell death) and has been implicated in several diseases, including cancer and neurodegenerative disorders. However, more research is needed to fully understand the functions and regulatory mechanisms of this protein.

Tetrabenazine is a prescription medication used to treat conditions associated with abnormal involuntary movements, such as chorea in Huntington's disease. It works by depleting the neurotransmitter dopamine in the brain, which helps to reduce the severity and frequency of these movements.

Here is the medical definition:

Tetrabenazine is a selective monoamine-depleting agent, with preferential uptake by dopamine neurons. It is used in the treatment of chorea associated with Huntington's disease. Tetrabenazine inhibits vesicular monoamine transporter 2 (VMAT2), leading to depletion of presynaptic dopamine and subsequent reduction in post-synaptic dopamine receptor activation. This mechanism of action is thought to underlie its therapeutic effect in reducing chorea severity and frequency.

(Definitions provided by Stedman's Medical Dictionary and American Society of Health-System Pharmacists)

In the context of medicine and pharmacology, "kinetics" refers to the study of how a drug moves throughout the body, including its absorption, distribution, metabolism, and excretion (often abbreviated as ADME). This field is called "pharmacokinetics."

1. Absorption: This is the process of a drug moving from its site of administration into the bloodstream. Factors such as the route of administration (e.g., oral, intravenous, etc.), formulation, and individual physiological differences can affect absorption.

2. Distribution: Once a drug is in the bloodstream, it gets distributed throughout the body to various tissues and organs. This process is influenced by factors like blood flow, protein binding, and lipid solubility of the drug.

3. Metabolism: Drugs are often chemically modified in the body, typically in the liver, through processes known as metabolism. These changes can lead to the formation of active or inactive metabolites, which may then be further distributed, excreted, or undergo additional metabolic transformations.

4. Excretion: This is the process by which drugs and their metabolites are eliminated from the body, primarily through the kidneys (urine) and the liver (bile).

Understanding the kinetics of a drug is crucial for determining its optimal dosing regimen, potential interactions with other medications or foods, and any necessary adjustments for special populations like pediatric or geriatric patients, or those with impaired renal or hepatic function.

Reserpine is an alkaloid derived from the Rauwolfia serpentina plant, which has been used in traditional medicine for its sedative and hypotensive effects. In modern medicine, reserpine is primarily used to treat hypertension (high blood pressure) due to its ability to lower both systolic and diastolic blood pressure.

Reserpine works by depleting catecholamines, including norepinephrine, epinephrine, and dopamine, from nerve terminals in the sympathetic nervous system. This leads to a decrease in peripheral vascular resistance and heart rate, ultimately resulting in reduced blood pressure.

Reserpine is available in various forms, such as tablets or capsules, and is typically administered orally. Common side effects include nasal congestion, dizziness, sedation, and gastrointestinal disturbances like diarrhea and nausea. Long-term use of reserpine may also lead to depression in some individuals. Due to its potential for causing depression, other antihypertensive medications are often preferred over reserpine when possible.

PC12 cells are a type of rat pheochromocytoma cell line, which are commonly used in scientific research. Pheochromocytomas are tumors that develop from the chromaffin cells of the adrenal gland, and PC12 cells are a subtype of these cells.

PC12 cells have several characteristics that make them useful for research purposes. They can be grown in culture and can be differentiated into a neuron-like phenotype when treated with nerve growth factor (NGF). This makes them a popular choice for studies involving neuroscience, neurotoxicity, and neurodegenerative disorders.

PC12 cells are also known to express various neurotransmitter receptors, ion channels, and other proteins that are relevant to neuronal function, making them useful for studying the mechanisms of drug action and toxicity. Additionally, PC12 cells can be used to study the regulation of cell growth and differentiation, as well as the molecular basis of cancer.

Electric capacitance is a measure of the amount of electrical charge that a body or system can hold for a given electric potential. In other words, it is a measure of the capacity of a body or system to store an electric charge. The unit of electric capacitance is the farad (F), which is defined as the capacitance of a conductor that, when charged with one coulomb of electricity, has a potential difference of one volt between its surfaces.

In medical terms, electric capacitance may be relevant in the context of electrical stimulation therapies, such as transcutaneous electrical nerve stimulation (TENS) or functional electrical stimulation (FES). In these therapies, electrodes are placed on the skin and a controlled electric current is applied to stimulate nerves or muscles. The electric capacitance of the tissue and electrodes can affect the distribution and intensity of the electric field, which in turn can influence the therapeutic effect.

It is important to note that while electric capacitance is a fundamental concept in physics and engineering, it is not a commonly used term in medical practice or research. Instead, terms such as impedance or resistance are more commonly used to describe the electrical properties of biological tissues.

"Endocrine System: adrenal gland, reticularis and medulla" Secretion Control in Adrenal Chromaffin Cells UC-San Diego Chromaffin ... In order to activate chromaffin cells, the splanchnic nerve of the sympathetic nervous system releases acetylcholine, which ... Perry, SF; Capaldo, A (Nov 16, 2011). "The autonomic nervous system and chromaffin tissue: neuroendocrine regulation of ... Chromaffin cells also settle near the vagus nerve and carotid arteries. In lower concentrations, extra-adrenal chromaffin cells ...
... neurosecretory cells connected to the central nervous system. The synthesis, storage (in chromaffin cells) and release of ... Gasman S, Chasserot-Golaz S, Bader MF, Vitale N (October 2003). "Regulation of exocytosis in adrenal chromaffin cells: focus on ... Unsicker K, Huber K, Schütz G, Kalcheim C (Jun-Jul 2005). "The chromaffin cell and its development". Neurochemical Research. 30 ... The adrenal medulla produces adrenomedullary hormones in chromaffin cells, cells which are very similar in structure to post- ...
Chromaffin cells of the adrenal medulla. Near the vertebral column and become sympathetic chain ganglia. Differentiation ... v t e (Embryology of nervous system, All stub articles, Developmental biology stubs). ... sclerotome to become the epinephrine-producing cells of the adrenal gland and the neurons of the sympathetic nervous system. ...
This makes PC12 cells useful as a model system for neuronal differentiation and neurosecretion. Treatment of PC12 cells with ... It was developed in parallel to the adrenal chromaffin cell model because of its extreme versatility for pharmacological ... Treatment of PC12 cells with dexamethasone differentiates them into chromaffin-like cells. Using patch clamp recording and ... and release of these neurotransmitters give rise to spikes due to changes in current similar to chromaffin cells. PC12 cell ...
The cardiovascular system is the most commonly involved. In pregnancy, pheochromocytoma is associated with significant maternal ... Pheochromocytoma is a rare tumor of the adrenal medulla composed of chromaffin cells, also known as pheochromocytes. When a ... The signs and symptoms of a pheochromocytoma are those related to sympathetic nervous system hyperactivity. The classic triad ... Metastatic pheochromocytoma is defined as the presence of tumor cells (chromaffin tissue) where they are not normally found. ...
SIFs are interneurons associated with the sympathetic nervous system which are managed by dopamine. VMAT1 is found in both ... Vesicular monoamine transporter 1 (VMAT1) also known as chromaffin granule amine transporter (CGAT) or solute carrier family 18 ... MAXHOM alignment was determined using the "profile-fed neural network systems from Heidelberg" (PHD) program. The main ... Specifically, VMAT1 is found in chromaffin cells, enterochromaffin cells, and small intensely fluorescent cells (SIFs). ...
Chromaffin cells are derived from the embryonic neural crest, and are modified postganglionic sympathetic neurons. They are ... Ganglioneuroma, a tumor in the nerve cells of the peripheral nervous system. The adrenal medulla may be poorly formed or absent ... Adrenal gland Chromaffin cell History of catecholamine research Carmichael, Stephen W. (1997-01-01), Bittar, E. Edward; Bittar ... As a cluster of neuron cell bodies, the adrenal medulla is considered a modified ganglion of the sympathetic nervous system. ...
July 2014). "A defined, controlled culture system for primary bovine chromaffin progenitors reveals novel biomarkers and ... Chromaffin progenitor cells of the bovine adrenal medulla. Mouse insulinoma cells (MIN6 cell line) and mouse pancreatic islet ... Cultured bovine chromaffin progenitor cells: Several activators of the signaling pathway increase cell yield. Cultured mouse ...
The VMAT were first isolated and purified in bovine chromaffin granules, in both its native and denatured forms. There are two ... In the 1970s, scientists like Arvid Carlsson recognized the need to understand how transport systems and ion gradients work in ... 1994). "The chromaffin granule and synaptic vesicle amine transporters differ in substrate recognition and sensitivity to ... VMAT1 is expressed mainly in large dense-core vesicles (LDCVs) of the peripheral nervous system. VMAT1 may be found in ...
In the autonomic nervous system, fibers from the ganglion to the effector organ are called postganglionic fibers. The ... Another notable structure is the medulla of the adrenal gland, where chromaffin cells function as modified post-ganglionic ... Preganglionic fibers Nerve fiber Noback C, Ruggiero DA, Demarest RJ, Strominger NL (2005). The Human Nervous System: Structure ... Like other components of the sympathetic nervous system, all of these exceptions are still stimulated by cholinergic ...
The insulin receptor system, in contrast, appears to diminish the efficacy of endosomal signaling. The epidermal growth factor ... In addition, they are functional in mediating communication pathways in cell types such as adrenal chromaffin, platelets, and ... Systems on which the organism relies malfunction, resulting often in cancers. Preventing this type of circumstance is highly ... Mammals possess this system, which begins in the kidneys where the developmental signal is manufactured. The developmental ...
... chromaffin cells of the adrenal gland and beta cells in the pancreas. In the central nervous system, Doc2b contributes to the ...
... is found in brain and throughout the neuroendocrine system, including the endocrine pancreas, pituitary, and ... purification and characterization of a specific enkephalin-synthesizing carboxypeptidase localized to adrenal chromaffin ... adrenal gland chromaffin cells. Within cells, carboxypeptidase E is present in the secretory granules along with its peptide ...
They are a neural crest derivative and share a common sympathoadrenal precursor cell with sympathetic neurons and chromaffin ... of the Sympathetic division of the autonomic nervous system (ANS). The neurotransmitter for these cells is dopamine. ... (Cell biology, Autonomic nervous system). ...
Nicotine Activity on Chromaffin Cells edit]] The interactive pathway map can be edited at WikiPathways: " ... while awake the thalamus should instead relay sensory inputs from outside the central nervous system. The mechanism of absence ...
... it also activates many other responses within the central nervous system reward system, which drives behavioral responses; ... While PNMT is found primarily in the cytosol of the endocrine cells of the adrenal medulla (also known as chromaffin cells), it ... Little adrenaline is found in other tissues, mostly in scattered chromaffin cells and in a small number of neurons that use ... Adrenaline is synthesized in the chromaffin cells of the adrenal gland's adrenal medulla and a small number of neurons in the ...
... functioning as part of the sympathetic nervous system (a branch of the autonomic nervous system). These cells normally act as ... Paragangliomas originate from paraganglia in chromaffin-negative glomus cells derived from the embryonic neural crest, ... Given the fact that they originate from cells of the orthosympathetic system, paragangliomas are closely related to ... comprising a small mass of neural crest-derived chromaffin cells. Serves as a common origin of abdominal paragangliomas. Vagal ...
The chromaffin cells of the medulla are the body's main source of the catecholamines, such as adrenaline and noradrenaline, ... The HPA axis is an example of a negative feedback system, in which cortisol itself acts as a direct inhibitor of both CRH and ... The HPA axis also interacts with the immune system through increased secretion of ACTH at the presence of certain molecules of ... Formation Catecholamines are produced in chromaffin cells in the medulla of the adrenal gland, from tyrosine, a non-essential ...
... produced mainly by the chromaffin cells of the adrenal medulla and the postganglionic fibers of the sympathetic nervous system ... Dopamine, which acts as a neurotransmitter in the central nervous system, is largely produced in neuronal cell bodies in two ... Catecholamine tests are done to identify rare tumors at the adrenal gland or in the nervous system. Catecholamine tests provide ... The catecholamine norepinephrine is a neuromodulator of the peripheral sympathetic nervous system but is also present in the ...
Chromaffin cells contained in the adrenal medulla act as postganglionic nerve fibers that release this chemical response into ... The sympathoadrenal system is a physiological connection between the sympathetic nervous system and the adrenal medulla and is ... muscles along with the muscles surrounding certain bodily systems such as the cardiovascular system and respiratory system, ... The sympathoadrenal system can activate and discharge chemical messengers as a single unit to activate an organism's "fight or ...
The sympathetic nervous system also has some preganglionic nerves terminating at the chromaffin cells in the adrenal medulla, ... The chromaffin cells of the adrenal medulla act as "modified neurons", releasing adrenaline and noradrenaline into the ... The somatic nervous system uses a nicotinic receptor to acetylcholine at the neuromuscular junction. Muscarinic acetylcholine ... Very few parts of the sympathetic system use cholinergic receptors. In sweat glands the receptors are of the muscarinic type. ...
Innervated by sympathetic nervous system, chromaffin cells are important in the initiation of the fight-or-flight response of ... In Göttingen Südhof worked on his doctoral thesis, in which he described the structure and function of chromaffin cells, at the ... Südhof described the structure and function of chromaffin cells which are responsible for the release of epinephrine, ...
It is expressed exclusively in the nervous system, in most neurons that control the viscera (cardiovascular, digestive and ... Essential for the differentiation and survival of sympathetic neurons and chromaffin cells, the transcription factor PHOX2B is ... Mutations in human PHOX2B cause a rare disease of the visceral nervous system (dysautonomia): congenital central ... partial agenesis of the enteric nervous system), ROHHAD, and tumours of the sympathetic ganglia. In most people, Exon 3 of the ...
The name is derived from their location in the enteric system and their chromaffin-like staining pattern in histologic sections ... List of distinct cell types in the adult human body Enterochromaffin cell Chromaffin cell List of human cell types derived from ...
When a distinction is made, the "aortic bodies" are chemoreceptors which regulate the circulatory system, while the "paraaortic ... bodies" are the chromaffin cells which manufacture catecholamines. The aortic bodies measure partial gas pressures and the ... Cardiovascular System", Pathobiology of Human Disease, San Diego: Academic Press, pp. 1042-1070, doi:10.1016/b978-0-12-386456- ...
They constitute an enteric endocrine system as a subset of the endocrine system just as the enteric nervous system is a subset ... Enterochromaffin-like cells are enteroendocrine and neuroendocrine cells also known for their similarity to chromaffin cells ... Histology image: 11604loa - Histology Learning System at Boston University - "Endocrine System: duodenum, enteroendocrine cells ... The very discovery of hormones occurred during studies of how the digestive system regulates its activities, as explained at ...
Chromaffin paraganglia (also called chromaffin bodies) are connected with the ganglia of the sympathetic trunk and the ganglia ... WHO classification of tumors (2005). "Tumours of the Paraganglionic System". Pathology and genetics of head and neck tumours ( ... Chromaffin paragangliomas are issued from chromaffin cells, and are known as pheochromocytomas. Adrenal pheochromocytomas are ... They are essentially of two types: (1) chromaffin or sympathetic paraganglia made of chromaffin cells and (2) nonchromaffin or ...
FSCV is used to study dynamics of exocytosis of noradrenaline and adrenaline from chromaffin cells; release of serotonin from ... ISBN 978-3-527-30250-5. Wightman, R. M. (2006). "Probing Cellular Chemistry in Biological Systems with Microelectrodes". ... Initially, FSCV was successfully used for detection of electrochemically active biogenic amines release in chromaffin cells ( ... and can only be used with select molecules in biological systems. In spite of this, there have been methods developed to ...
Immune cells of both the Innate immune system and adaptive immune systems frequently express the α2, α5, α6, α7, α9, and α10 ... Calcium triggers the exocytosis of chromaffin granules and thus the release of epinephrine (and norepinephrine) into the ... Dickson SL, Egecioglu E, Landgren S, Skibicka KP, Engel JA, Jerlhag E (June 2011). "The role of the central ghrelin system in ... POMC neurons are a precursor of the melanocortin system, a critical regulator of body weight and peripheral tissue such as skin ...
... chromaffin system, et al. He was married to the Galician-Austrian writer, journalist and critic Berta Szeps. The couple's house ...
"Endocrine System: adrenal gland, reticularis and medulla" Secretion Control in Adrenal Chromaffin Cells UC-San Diego Chromaffin ... In order to activate chromaffin cells, the splanchnic nerve of the sympathetic nervous system releases acetylcholine, which ... Perry, SF; Capaldo, A (Nov 16, 2011). "The autonomic nervous system and chromaffin tissue: neuroendocrine regulation of ... Chromaffin cells also settle near the vagus nerve and carotid arteries. In lower concentrations, extra-adrenal chromaffin cells ...
... catecholamine-secreting tumor derived from chromaffin cells. The term pheochromocytoma (in Greek, phios means dusky, chroma ... Extra-adrenal pheochromocytomas develop in the paraganglion chromaffin tissue of the nervous system. They may occur anywhere ... Assignment of PGL3 to chromosome 1 (q21-q23) in a family with autosomal dominant non-chromaffin paraganglioma. Am J Med Genet. ... A pheochromocytoma (see the image below) is a rare, catecholamine-secreting tumor derived from chromaffin cells. The term ...
endocrine system * adrenal gland *adrenal vessels *adrenal arteries. *adrenal veins. *chromaffin cells ...
The hypothalamic neurosecretory system is poorly developed in the most primitive of the living Agnatha vertebrates, the ... Endocrine system - Hypothalamic, Pituitary, Target Organs: The hypothalamic-pituitary-target organ axes of all vertebrates are ... In fishes the interrenal and chromaffin cells often are embedded in the kidneys, whereas in amphibians they are distributed ... The hypothalamic neurosecretory system is poorly developed in the most primitive of the living Agnatha vertebrates, the ...
... catecholamine-secreting tumor derived from chromaffin cells. The term pheochromocytoma (in Greek, phios means dusky, chroma ... Extra-adrenal pheochromocytomas develop in the paraganglion chromaffin tissue of the nervous system. They may occur anywhere ... Assignment of PGL3 to chromosome 1 (q21-q23) in a family with autosomal dominant non-chromaffin paraganglioma. Am J Med Genet. ... A pheochromocytoma (see the image below) is a rare, catecholamine-secreting tumor derived from chromaffin cells. The term ...
Neural crest cells differentiate into diverse cell types, including neurons of various peripheral nervous systems, Schwann ... cells, melanocytes, skin pigment cells, chromaffin cells such as adrenal medullae, smooth muscle of the heart, facial bone and ... For Comprehensive Healthcare System for Children as well as Families and Society -," operates cell therapy (regenerative ... 4 is expected to be applied to disease of nervous and musculoskeletal system. Through in-house and collaborative researches, ...
... sympathetic nervous system-chromaffin cells, which results in the release of catecholamines (adrenaline and noroadrenaline) as ... Physiology of fish in intensive culture systems. New York, Chapman and Hall, 232p. ... Ammonia in Aquatic Systems. Available online at: [Accessed: 06/10/2013]. ...
Chromaffin cells of the adrenal medulla: physiology, pharmacology, and disease. Compr Physiol. 2019;9(4):1443-1502.. View this ... Furthermore, we identified the dopamine (DA) midbrain system as one key brain circuit affected by this CACNA1D channelopathy ... Gating changes of LTCC Ca2+ currents and altered firing in adrenal chromaffin cells from HET Cav1.3AG mice. Since we detected ... Impaired chromaffin cells excitability and exocytosis in autistic Timothy syndrome TS2-neo mouse rescued by L-type calcium ...
Chromaffin cell neoplasm Active Synonym false false 506611012 Chromaffin tumour Active Synonym false false ... Code System Concept Name. Pheochromocytoma (morphologic abnormality). Code System Preferred Concept Name. Pheochromocytoma ( ... Code System Concept Code System Concept Code. 85583005. ... Code System Code. PH_SNOMED-CT Code System OID. 2.16.840.1. ...
Chromaffin System (1966-1972). Nerve Tissue Proteins (1966-1972). Public MeSH Note:. 1991; see NERVE TISSUE PROTEINS 1973-1990 ...
The auxiliary systems now done at presentation with nipple sahebkar a placebo vs. The water-resistant protein kinase inhibitors ... Jones criteria compared to immature oocytes and chromaffin cells for mood. Duggan ma, platelets normalize levels drop in ... In the driver gets around a survey system and introduction produces a common presenting injection of health risks. Orexin ...
In addition to the ENDOCRINE GLANDS, included are the CHROMAFFIN SYSTEM and the NEUROSECRETORY SYSTEMS. ... Sistema Endocrino 1 quesito The system of glands that release their secretions (hormones) directly into the circulatory system ... In humans, the digestive system includes the GASTROINTESTINAL TRACT and the accessory glands (LIVER; BILIARY TRACT; PANCREAS). ... It contains the chief organs of the circulatory and respiratory systems. (From Stedman, 25th ed) ...
... catecholamine-secreting tumor derived from chromaffin cells. The term pheochromocytoma (in Greek, phios means dusky, chroma ... Extra-adrenal pheochromocytomas develop in the paraganglion chromaffin tissue of the nervous system. They may occur anywhere ... Assignment of PGL3 to chromosome 1 (q21-q23) in a family with autosomal dominant non-chromaffin paraganglioma. Am J Med Genet. ... A pheochromocytoma is a rare, catecholamine-secreting tumor derived from chromaffin cells. The term pheochromocytoma (in Greek ...
... catecholamine-secreting tumor derived from chromaffin cells. The term pheochromocytoma (in Greek, phios means dusky, chroma ... Extra-adrenal pheochromocytomas develop in the paraganglion chromaffin tissue of the nervous system. They may occur anywhere ... Assignment of PGL3 to chromosome 1 (q21-q23) in a family with autosomal dominant non-chromaffin paraganglioma. Am J Med Genet. ... A pheochromocytoma is a rare, catecholamine-secreting tumor derived from chromaffin cells. The term pheochromocytoma (in Greek ...
Paragangliomas are neuroendocrine tumors derived from chromaffin cells of the extraadrenal sympathetic system; mediastinal ... Paragangliomas are neuroendocrine tumors derived from chromaffin cells of the extraadrenal sympathetic system; mediastinal ...
Automated imaging system for fast quantitation of neurons, cell morphology and neurite morphometry in vivo and in vitro.. ... The BAR domain protein PICK1 controls vesicle number and size in adrenal chromaffin cells.. The Journal of neuroscience : the ... Enhanced central nervous system transduction with lentiviral vectors pseudotyped with RVG/HIV-1gp41 chimeric envelope ... and behavioral impact of AAV2/5-mediated overexpression of human wildtype alpha-synuclein in the rat nigrostriatal system.. ...
The physiology of the hypothalamic-pituitary-adrenocortical system Overview of the Endocrine System The endocrine system ... The adrenal medulla is composed of chromaffin cells, which synthesize and secrete catecholamines (mainly epinephrine and lesser ... Glucocorticoids promote and inhibit gene transcription in many cells and organ systems. Prominent effects include anti- ... the major effector amines of the sympathetic nervous system, are responsible for the "flight or fight" response (ie, ...
They develop in many parts of central nervous system (CNS) and beyond it - in chromaffin tissue and adrenal medulla, diffuse ... leucocytes and immune system cells, skeletal system and other elements of locomotor system, bone marrow, gastrointestinal tract ... Respiratory system diseases.. Urogenital system disorders.. Neoplastic processes.. Long-lasting vasoconstriction in ... and stress-limiting systems, which restrict the activation of stress-system and damaging influence of stress-hormones.. Stress- ...
PHEOs are derived from the chromaffin cells of the adrenal medulla, and SPGLs are found in close relationship to the peripheral ... sympathetic nervous system from the level of the superior cervical ganglion down the trunk into the pelvis.[7] Metastases are ...
2000) Real-time measurements of vesicle-SNARE recycling in synapses of the central nervous system. Nat Cell Biol 2:197-204. ... 1993) Multiple calcium-dependent processes related to secretion in bovine chromaffin cells. Neuron 10:21-30. ... 1B-F, 2-7). Photoactivation experiments were conducted using a single, spot-focused, 405 nm laser on the cellTIRF system. ... 1A). Images were also captured on an Olympus IX83 inverted microscope equipped with a cellTIRF 4Line excitation system using an ...
It will be interesting to find out the effect of TH on the inflammatory system in vivo, as well as its effect on other types of ... 5f). Rab27a has also been shown to be involved in exocytosis of insulin and chromaffin granules in endocrine cells. Autocrine ... The signals were visualized using LiCor Odyssey Infrared Imaging System after reaction with goat anti-mouse IRDye 680LT, or ... The signal was detected using the OdysseyFc Imaging System (LI-COR, Inc., NE, USA). All protein quantifications were normalized ...
Hoffmann C, Ziegler U, Buschmann A, Weber A, Kupfer L, Oelschlegel A, Prions spread via the autonomic nervous system from the ... We provisionally categorized the adrenal gland as nerve tissue because of the presence of chromaffin cells in the medulla of ... L-type BSE prions propagated in the central nervous system and were spread centrifugally by nerve pathways (11,12). In Italy, L ... in the central nervous system. The scientific literature in general has assumed that BSE in cattle is caused by a uniform ...
Paraganglioma, Paraganglia, Chromaffin, Carotid Body Tumor, Nuclear Medicine Hemangioma gigante da parede torácica: localização ... Health Systems 21 * Science and Technology Information Networks 21 * Financial Resources in Health 20 ...
Urogenital System Spherocytes. Small, abnormal spherical red blood cells with more than the normal amount of hemoglobin. ...
Early Stages of the Development of the Nervous System.-No definite trace of the nervous system is present until the primitive ... and masses of chromaffin cells. (3) The formation of the anterior and posterior nerve-roots. (4) The differentiation of the ... The Intermediate Cell Tracts.-The intermediate cell tracts are the rudiments of the internal organs of the genital system and ... the temporary and permanent urinary system, with the exception of the urinary bladder and the urethra. ...
Samples from tissues from the kidney and digestive system were fixed after disassociation to deactivate endogenous RNases and ... Intestine-Chromaffin cells. Intestine-ENS glia. Intestine-ENS neurons. Intestine-Erythroblasts. Intestine-Intestinal epithelial ...
Wiebke Arlt Institute of Metabolism and Systems Research, University of Birmingham. Centre for Endocrinology, Diabetes and ... Elective adrenalectomy revealed an adrenal tumour consisting of chromaffin cells intermixed with breast carcinoma cells. ... Vasileios Chortis Institute of Metabolism and Systems Research, University of Birmingham. Centre for Endocrinology, Diabetes ...
It is recommended that this reagent should be titrated in each testing system to obtain optimal results. ... Removing a 9 amino acid sequence of SNAP-25 inhibited neurosecretion in chromaffin cells. ...
  • These terms can be used interchangeably but usually paraganglioma refer to a tumor originating from chromaffin cells outside the adrenal gland, which can also be called extra-adrenal pheochromocytoma, whereas pheochromocytoma typically refer to a tumor originating from the chromaffin cells within the adrenal gland. (
  • Its latest findings from the study take things a step further while also explaining DehydraTECH-CBD's interaction with the sympatho-chromaffin system via catestatin modulation. (
  • Details of the Study The group of researchers from Croatia studied how the sympatho-chromaffin system (catestatin peptides) is involved in CBD-induced blood pressure reduction. (
  • A pheochromocytoma (see the image below) is a rare, catecholamine-secreting tumor derived from chromaffin cells. (
  • Se analizaron el tamaño ganglionar y del tumor primario en la TC, y su valoración cualitativa y semicuantitativa (SUVmáx) en la PET. (
  • Pheochromocytoma A pheochromocytoma is a catecholamine-secreting tumor of chromaffin cells typically located in the adrenals. (
  • Paraganglioma is a rare neuroendocrine tumor that arises from the cells of the neuroendocrine system. (
  • The chromaffin cells release catecholamines: ~80% of adrenaline (epinephrine) and ~20% of noradrenaline (norepinephrine) into systemic circulation for systemic effects on multiple organs (similarly to secretory neurones of the hypothalamus), and can also send paracrine signals. (
  • This increased sympathetic activity leads to chronically increased synthesis and secretion of catecholamines from the adrenal chromaffin cells. (
  • This chronic increase of epinephrine and norepinephrine secretion causes desensitization of the chromaffin cells to catecholamines resulting in a decrease in production and presence of α2 adrenergic receptors on their cell membrane. (
  • Moreover, the sympathetic-related regions of the brain, located in the vicinity of the paraventricular nucleus, hypothalamus, and brainstem nuclei, stimulate release of catecholamines from chromaffin cells of the adrenal medulla fig. Randomised trial of oral and intravenous methylprednisolone in acute relapses of multiple sclerosis. (
  • We provisionally categorized the adrenal gland as nerve tissue because of the presence of chromaffin cells in the medulla of the gland. (
  • 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 nerve of the sympathetic nervous system releases acetylcholine, which then binds to nicotinic acetylcholine receptors on the adrenal medulla. (
  • There are two types of cells that originate from the neural crest and are related to the sympathetic nervous system (originate from a cell called sympathogonia): 1) Neuroblasts: These cells migrate, during the fourth to the fifth week of fetal development in humans, on both sides of the spinal cord toward the region just behind the dorsal aorta forming the two chains of sympathetic ganglia (Sympathetic chain). (
  • The secreted adrenaline and noradrenaline play an important role in the sympathetic nervous system response, commonly called the fight-or-flight response. (
  • There are (i.) a series of isolated masses, the paraganglia, associated singly or in groups with the ganglia of the sympathetic nervous system, (ii. (
  • And that extra GABA may be absolutely necessary for an individual with a ramped-up sympathetic nervous system. (
  • Catestatin is an inhibitor of the sympathetic nervous system. (
  • [ 6 ] PHEOs are derived from the chromaffin cells of the adrenal medulla, and SPGLs are found in close relationship to the peripheral sympathetic nervous system from the level of the superior cervical ganglion down the trunk into the pelvis. (
  • The largest extra-adrenal cluster of chromaffin cells in mammals is the organ of Zuckerkandl. (
  • In lower concentrations, extra-adrenal chromaffin cells also reside in the bladder wall, prostate, and behind the liver. (
  • Extra-adrenal pheochromocytomas develop in the paraganglion chromaffin tissue of the nervous system. (
  • Paragangliomas are neuroendocrine tumors that originate from the chromaffin cells of the extra-adrenal paraganglia. (
  • Chromaffin cells of the adrenal medulla are innervated by the splanchnic nerve and secrete adrenaline (epinephrine), noradrenaline (norepinephrine), some dopamine, enkephalin and enkephalin-containing peptides, and a few other hormones into the blood stream. (
  • When splanchnic nerve cells trigger a stress response, chromaffin cells release their granules. (
  • 2) Chromaffin cells (or pheochromocytes): These cells will migrate to the area adjacent to the sympathetic ganglia (hence the name paraganglia) and to the adrenal medulla where they will be the most abundant type of cells. (
  • The paraganglia are rounded masses of chromaphil tissue, 1-3 mm. in diameter, placed inside, half inside, or immediately outside the capsules of the ganglia of the sympathetic system. (
  • In non-mammals, chromaffin cells are found in a variety of places, generally not organised as an individual organ, and may be without innervation, relying only on endocrine or paracrine signals for secretion. (
  • Overview of the Endocrine System The endocrine system coordinates functioning between different organs through hormones, which are chemicals released into the bloodstream from specific types of cells within endocrine (ductless). (
  • The distribution of the masses of tissue forming the system is shown in Fig. 1053. (
  • They develop in many parts of central nervous system (CNS) and beyond it - in chromaffin tissue and adrenal medulla, diffuse endocrinocytes of gastrointestinal tract and bronchi and even in T-lymphocytes. (
  • In fact, it acts in an autocrine/paracrine manner when released from adrenal chromaffin cells, which live in close vicinity to the excitatory catecholamine-releasing sympathetic neurons. (
  • The difference in meat quality between Hanwoo and Holstein could originate from differential evolution of the genes related to these blood and circulatory system ontology terms. (
  • Neoplasms arising from these cells are pheochromocytomas (also called chromaffin or sympathetic paragangliomas, in contrast to non-chromaffin or parasympathetic paragangliomas of glomus cells). (
  • the spleen and the glomus coccygeum, which are associated with the circulatory system. (
  • Chromaffin cells also settle near the vagus nerve and carotid arteries. (
  • Chromaffin cells, also called pheochromocytes (or phaeochromocytes), are neuroendocrine cells found mostly in the medulla of the adrenal glands in mammals. (
  • The genes that distinguish Hanwoo from Holstein in terms of substitution rate predominantly have gene ontology terms related to blood and circulatory system. (
  • SHED, which are dental pulp stem cells derived from neural crest cells,* 4 is expected to be applied to disease of nervous and musculoskeletal system. (
  • This nerve is part of your autonomic nervous system. (
  • GABA - Gamma-aminobutyric acid , is the neurotransmitter known for its affinity for GABA receptors throughout the central nervous system (CNS). (
  • GABA made and stored in the nerves of the enteric nervous system acts to mediate the upper gastrointestinal tract's secretion and emptying mechanisms and modulate the sensation of visceral pain there. (
  • Bovine spongiform encephalopathy (BSE) is a fatal neurodegenerative disorder of cattle characterized by accumulation of a protease-resistant form of a normal cellular prion protein (PrPres) in the central nervous system. (
  • NECTAR - the network for European CNS transplantation and restoration was founded over 25 years ago with the aim of bringing together European groups who share the common goal of protecting, repairing, and restoring the central nervous system from damage caused by degenerative disease or injury. (
  • The idea of transplanting cel s to the nervous system emerged in the 1970s, in the 1980s we saw also the first attempts to apply this idea in patients. (
  • Gamma-amino-butyric acid (GABA) serves as inhibitory transmitter in stress-limiting systems of hypothalamus. (
  • Intensity of stress response is determined by the correlation of activation of stress-system, which realizes the response of an organism to stress, and stress-limiting systems, which restrict the activation of stress-system and damaging influence of stress-hormones. (
  • The delicate balance in the brain between GABA and glutamate is orchestrated by shuttle systems from the Krebs Cycle, the presence of NMDA and GABA receptor modulators, enzyme cofactors, and reuptake mediators. (
  • Those with minor genetic mutations in the GAD enzyme system or those with autoantibodies against GAD may have lower GABA levels in the urine along with the symptom of disturbed sleep. (
  • Glucocorticoids promote and inhibit gene transcription in many cells and organ systems. (
  • The central part is represented by medullar and hypothalamic nuclei, the peripheral one is represented by hypothalamic pituitary-adrenal axis and efferent sympatic system. (
  • Structures, where all kinds of endogenic opiates are represented, are hypothalamic pituitary neurosecretary complex, limbic system, hippocamp and also components of inspiratory centre. (
  • The hypothalamic neurosecretory system is poorly developed in the most primitive of the living Agnatha vertebrates, the hagfishes, but all of the basic rudiments are present in the closely related lampreys. (
  • Opiate-ergic systems restrict destructive potential of stress response, prevent distress and favour physiological recovery from acute stress. (
  • Nitrogen oxide (NO), which is a universal factor of regulation of physiological systems and genetic apparatus of cells, plays an important role in stress-response mechanisms and adaptation of an organism to stress (Malyshev et al, 1998). (
  • Stress-system is divided into central and peripheral parts. (
  • Stress-limiting systems are also divided into central and peripheral parts. (
  • If cells have a greater numerical aperture, as is true with chromaffin cells, it will become difficult to acquire TIRF images utilizing the conventional objectives. (
  • In the driver gets around a survey system and introduction produces a common presenting injection of health risks. (

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