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Enterochromaffin
Enterochromaffin (EC) cells (also known as Kulchitsky cells) are a type of enteroendocrine cell, and neuroendocrine cell. They reside alongside the epithelium lining the lumen of the digestive tract and play a crucial role in gastrointestinal regulation, particularly intestinal motility and secretion. They were discovered by Nikolai Kulchitsky. EC cells modulate neuron signalling in the enteric nervous system (ENS) via the secretion of the neurotransmitter serotonin and other peptides. As enteric afferent and efferent nerves do not protrude into the intestinal lumen, EC cells act as a form of sensory transduction. However, recent research has shown the direct vagal connection to a specialized entero-endocrine cell, the neuropod cell. ECs known as neuropod cells rapidly relay signals from gut to brain via a direct communication with vagal and primary sensory neurons. Serotonin in the ENS acts in synergy with other digestive hormones to regulate sensory and motor gastroin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enterochromaffin-like Cells
Enterochromaffin-like cells or ECL cells are a type of neuroendocrine cell found in the gastric glands of the gastric mucosa beneath the epithelium, in particular in the vicinity of parietal cells, that aid in the production of gastric acid via the release of histamine. They are also considered a type of enteroendocrine cell. Function ECL cells synthesize and secrete histamine. These cells are stimulated by the hormones gastrin (not depicted in the adjacent diagram) and pituitary adenylyl cyclase-activating peptide. G cells are stimulated by vagal stimulation through the neurotransmitter gastrin-releasing peptide; this causes the G cells to secrete gastrin, which in turn stimulates ECL cells to release histamine. Note that this circuit is not activated by acetylcholine (ACh), which is of particular importance because the administration of atropine will not block the vagal stimulation of the G cells, as ACh is not the neurotransmitter for these cells. However, ECL cells are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enteroendocrine Cell
Enteroendocrine cells are specialized cells of the gastrointestinal tract and pancreas with endocrine function. They produce gastrointestinal hormones or peptides in response to various stimuli and release them into the bloodstream for systemic effect, diffuse them as local messengers, or transmit them to the enteric nervous system to activate nervous responses. Enteroendocrine cells of the intestine are the most numerous endocrine cells of the body. They constitute an enteric endocrine system as a subset of the endocrine system just as the enteric nervous system is a subset of the nervous system. In a sense they are known to act as chemoreceptors, initiating digestive actions and detecting harmful substances and initiating protective responses. Enteroendocrine cells are located in the stomach, in the intestine and in the pancreas. Microbiota play key roles in the intestinal immune and metabolic responses in these enteroendocrine cells via their fermentation product ( short chain ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Distinct Cell Types In The Adult Human Body
The list of human cell types provides an enumeration and description of the various specialized cells found within the human body, highlighting their distinct functions, characteristics, and contributions to overall physiological processes. Cells may be classified by their physiological function, histology (microscopic anatomy), lineage, or gene expression. Total number of cells The adult human body is estimated to contain about 30 trillion (3×1013) human cells, with the number varying between 20 and 100 trillion depending on factors such as sex, age, and weight. Additionally, there are approximately an equal number of bacterial cells. The exact count of human cells has not yet been empirically measured in its entirety and is estimated using different approaches based on smaller samples of empirical observation. It is generally assumed that these cells share features with each other and thus may be organized as belonging to a smaller number of types. Classification ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Human Cell Types Derived From The Germ Layers
This is a list of Cell (biology), cells in humans derived from the three embryonic germ layers – ectoderm, mesoderm, and endoderm. Cells derived from ectoderm Surface ectoderm Skin * Trichocyte (human), Trichocyte * Keratinocyte Anterior pituitary * Gonadotropic cell, Gonadotrope * Corticotropic cell, Corticotrope * Thyrotropic cell, Thyrotrope * Somatotropic cell, Somatotrope * Prolactin cell, Lactotroph Tooth enamel * Ameloblast Neural crest Peripheral nervous system * Neuron * Neuroglia, Glia ** Schwann cell ** Satellite glial cell Neuroendocrine system * Chromaffin cell * Glomus cell Skin * Melanocyte ** Nevus cell * Merkel cell Teeth * Odontoblast * Cementoblast Eyes * Corneal keratocyte Smooth muscle Neural tube Central nervous system * Neuron * Glia ** Astrocyte ** Ependyma, Ependymocytes ** Müller glia (retina) ** Oligodendrocyte ** Oligodendrocyte progenitor cell ** Pituicyte (posterior pituitary) Pineal gland * Pinealocyte Cells derived from mesoderm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vesicular Monoamine Transporter 1
Vesicular monoamine transporter 1 (VMAT1), also known as chromaffin granule amine transporter (CGAT) or solute carrier family 18 member 1 (SLC18A1), is a protein that in humans is encoded by the ''SLC18A1'' gene. VMAT1 is an integral membrane protein, which is embedded in synaptic vesicles and serves to transfer monoamines, such as norepinephrine, epinephrine, dopamine, and serotonin, between the cytosol and synaptic vesicles. SLC18A1 is an isoform of the vesicular monoamine transporter. Discovery The idea that there must be specific transport proteins associated with the uptake of monoamines and acetylcholine into vesicles developed due to the discovery of specific inhibitors which interfered with monoamine neurotransmission and also depleted monoamines in neuroendocrine tissues. VMAT1 and VMAT2 were first identified in rats upon cloning cDNAs for proteins which gave non-amine accumulating recipient cells the ability to sequester monoamines. Subsequently, human VMATs were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nikolai Kulchitsky
Nikolai Konstantinovich Kulchitsky (; 16 January 1856, Kronstadt – 30 January 1925, Oxford) was a Russian anatomist and histologist, the last Minister of Education of the Russian Empire. Born into an old untitled noble family of Polish origin, he was the second son of Konstantin Petrovich Kulchitsky (b. 1827), a naval officer, and his wife, Elizaveta Prokofyevna Pavlova, daughter of a Colonel in Russian Imperial army.http://www.russiangrave.ru/person?prs_id=26 In 1874–1879 he studied at the Medical Faculty of Kharkiv Imperial University. In 1882 he became a doctor of medicine. In 1893 he became professor of histology at the university of Kharkiv, and was later appointed director of education in . In 1897 he described the endocrine cells of the small intestine which now bear his name ( Kulchitsky cells). In 1906 Kulchitsky was a member of council of Kharkiv branch of The Union of Russian People. In 1916 he was appointed Minister of Education of the Russian Empire, a post he h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuropod Cell
A neuropod cell is a specialized enteroendocrine cell (i.e., sensory epithelial cell) within the gut that is capable of synapsing with afferent nerves. Previously, transmission of sensory signals from enteroendocrine cells were thought to only occur in a paracrine fashion, in which secreted peptide hormones diffused through the lamina propria and contacted either intrinsic or extrinsic neurons, entered the circulation, and/or acted on specific target tissues. However, neuropod cells, discovered by Dr. Diego V. Bohórquez in 2015 and later coined in 2018, were observed forming synaptic connections with nerves in the mucosa of the small and large intestine of rodents. These synapses were revealed to involve neurons originating from the dorsal root ganglia and the vagal nodose ganglia of the spinal cord, which suggested that sensory information from the gut lumen could be conveyed to the brain within milliseconds of activation. Also, it was found that these neuropod cells contained bot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, memory, and physiological processes such as vomiting and vasoconstriction. In the CNS, serotonin regulates mood, appetite, and sleep. Most of the body's serotonin—about 90%—is synthesized in the gastrointestinal tract by enterochromaffin cells, where it regulates intestinal movements. It is also produced in smaller amounts in the brainstem's raphe nuclei, the skin's Merkel cells, pulmonary neuroendocrine cells, and taste receptor cells of the tongue. Once secreted, serotonin is taken up by platelets in the blood, which release it during clotting to promote vasoconstriction and platelet aggregation. Around 8% of the body's serotonin is stored in platelets, and 1–2% is found in the CNS. Serotonin acts as both a vasoconstrictor and vas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuroendocrine Cell
Neuroendocrine cells are cells that receive neuronal input (through neurotransmitters released by nerve cells or neurosecretory cells) and, as a consequence of this input, release messenger molecules (hormones) into the blood. In this way they bring about an integration between the nervous system and the endocrine system, a process known as neuroendocrine integration. An example of a neuroendocrine cell is a cell of the adrenal medulla (innermost part of the adrenal gland), which releases adrenaline to the blood. The adrenal medullary cells are controlled by the sympathetic division of the autonomic nervous system. These cells are modified postganglionic neurons. Autonomic nerve fibers lead directly to them from the central nervous system. The adrenal medullary hormones are kept in vesicles much in the same way neurotransmitters are kept in neuronal vesicles. Hormonal effects can last up to ten times longer than those of neurotransmitters. Sympathetic nerve fiber impulses stimulat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcinoid Syndrome
Carcinoid syndrome is a paraneoplastic syndrome comprising the signs and symptoms that occur secondary to neuroendocrine tumors (formerly known as carcinoid tumors). The syndrome is caused by neuroendocrine tumors most often found in the gut releasing biologically active substances into the blood causing symptoms such as flushing and diarrhea, and less frequently, heart failure, vomiting and bronchoconstriction. Signs and symptoms The carcinoid syndrome occurs in approximately 10% of all neuroendocrine tumors or about 30–40% of more advanced/well developed neuroendocrine tumors. The biologically active substances that are released by the tumors cause the symptoms of the carcinoid syndrome. These substances act on the vessels to produce the symptoms of the carcinoid syndrome. * Flushing: The most common finding is flushing of the skin, usually of the head and the upper part of thorax in about 85% of people. The flushing may come and go and may also be triggered by variou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irritable Bowel Syndrome
Irritable bowel syndrome (IBS) is a functional gastrointestinal disorder characterized by a group of symptoms that commonly include abdominal pain, abdominal bloating, and changes in the consistency of bowel movements. These symptoms may occur over a long time, sometimes for years. IBS can negatively affect quality of life and may result in missed school or work or reduced productivity at work. Disorders such as anxiety, major depression, and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) are common among people with IBS.The cited review is based on sources ranging from 1988 to 2001 and is probably biased relative to a more recent research. The cause of IBS is not known but multiple factors have been proposed to lead to the condition. Theories include combinations of " gut–brain axis" problems, alterations in gut motility, visceral hypersensitivity, infections including small intestinal bacterial overgrowth, neurotransmitters, genetic factors, and food ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tryptophan Hydroxylase 1
Tryptophan hydroxylase 1 (TPH1) is an isoenzyme of tryptophan hydroxylase which in humans is encoded by the ''TPH1'' gene. TPH1 was first discovered to support serotonin synthesis in 1988 by converting tryptophan into 5-hydroxytryptophan. It was thought that there only was a single ''TPH'' gene until 2003. A second form was found in the mouse (''Tph2''), rat and human brain ( TPH2) and the original TPH was then renamed to TPH1. Function Tryptophan hydroxylases catalyze the biopterin-dependent monooxygenation of tryptophan to 5-hydroxytryptophan (5-HTP), which is subsequently decarboxylated by aromatic amino acid decarboxylase to form the neurotransmitter serotonin (5-hydroxytryptamine or 5-HT). It is the rate-limiting enzyme in the biosynthesis of serotonin. TPH expression is limited to a few specialized tissues: raphe neurons, pinealocytes, mast cells, mononuclear leukocytes, beta-cells of the islets of Langerhans, and intestinal and pancreatic enterochromaffin cells. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
