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Gut Motility
Peristalsis ( , ) is a radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an anterograde direction. Peristalsis is progression of coordinated contraction of involuntary circular muscles, which is preceded by a simultaneous contraction of the longitudinal muscle and relaxation of the circular muscle in the lining of the gut. In much of a digestive tract such as the human gastrointestinal tract, smooth muscle tissue contracts in sequence to produce a peristaltic wave, which propels a ball of food (called a bolus before being transformed into chyme in the stomach) along the tract. The peristaltic movement comprises relaxation of circular smooth muscles, then their contraction behind the chewed material to keep it from moving backward, then longitudinal contraction to push it forward. Earthworms use a similar mechanism to drive their locomotion, and some modern machinery imitate this design. The word comes from New Latin and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peristaltic
Peristalsis ( , ) is a radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an anterograde direction. Peristalsis is progression of coordinated contraction of involuntary circular muscles, which is preceded by a simultaneous contraction of the longitudinal muscle and relaxation of the circular muscle in the lining of the gut. In much of a digestive tract such as the human gastrointestinal tract, smooth muscle tissue contracts in sequence to produce a peristaltic wave, which propels a ball of food (called a bolus before being transformed into chyme in the stomach) along the tract. The peristaltic movement comprises relaxation of circular smooth muscles, then their contraction behind the chewed material to keep it from moving backward, then longitudinal contraction to push it forward. Earthworms use a similar mechanism to drive their locomotion, and some modern machinery imitate this design. The word comes from New Latin and i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serotonin
Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vasoconstriction. Approximately 90% of the serotonin that the body produces is in the intestinal tract. Biochemically, the indoleamine molecule derives from the amino acid tryptophan, via the (rate-limiting) hydroxylation of the 5 position on the ring (forming the intermediate 5-hydroxytryptophan), and then decarboxylation to produce serotonin. Serotonin is primarily found in the enteric nervous system located in the gastrointestinal tract (GI tract). However, it is also produced in the central nervous system (CNS), specifically in the raphe nuclei located in the brainstem, Merkel cells located in the skin, pulmonary neuroendocrine cells and taste receptor cells in the tongue. Additionally, serotonin is stored in blood platelets a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophagus
The esophagus (American English) or oesophagus (British English; both ), non-technically known also as the food pipe or gullet, is an organ in vertebrates through which food passes, aided by peristaltic contractions, from the pharynx to the stomach. The esophagus is a fibromuscular tube, about long in adults, that travels behind the trachea and heart, passes through the diaphragm, and empties into the uppermost region of the stomach. During swallowing, the epiglottis tilts backwards to prevent food from going down the larynx and lungs. The word ''oesophagus'' is from Ancient Greek οἰσοφάγος (oisophágos), from οἴσω (oísō), future form of φέρω (phérō, “I carry”) + ἔφαγον (éphagon, “I ate”). The wall of the esophagus from the lumen outwards consists of mucosa, submucosa (connective tissue), layers of muscle fibers between layers of fibrous tissue, and an outer layer of connective tissue. The mucosa is a stratified squamous epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Abdominal Muscles
The abdomen (colloquially called the belly, tummy, midriff, tucky or stomach) is the part of the body between the thorax (chest) and pelvis, in humans and in other vertebrates. The abdomen is the front part of the abdominal segment of the torso. The area occupied by the abdomen is called the abdominal cavity. In arthropods it is the posterior tagma of the body; it follows the thorax or cephalothorax. In humans, the abdomen stretches from the thorax at the thoracic diaphragm to the pelvis at the pelvic brim. The pelvic brim stretches from the lumbosacral joint (the intervertebral disc between L5 and S1) to the pubic symphysis and is the edge of the pelvic inlet. The space above this inlet and under the thoracic diaphragm is termed the abdominal cavity. The boundary of the abdominal cavity is the abdominal wall in the front and the peritoneal surface at the rear. In vertebrates, the abdomen is a large body cavity enclosed by the abdominal muscles, at front and to the sides, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vomiting
Vomiting (also known as emesis and throwing up) is the involuntary, forceful expulsion of the contents of one's stomach through the mouth and sometimes the nose. Vomiting can be the result of ailments like food poisoning, gastroenteritis, pregnancy, motion sickness, or hangover; or it can be an after effect of diseases such as brain tumors, elevated intracranial pressure, or overexposure to ionizing radiation. The feeling that one is about to vomit is called nausea; it often precedes, but does not always lead to vomiting. Impairment due to alcohol or anesthesia can cause inhalation of vomit, leading to suffocation. In severe cases, where dehydration develops, intravenous fluid may be required. Antiemetics are sometimes necessary to suppress nausea and vomiting. Self-induced vomiting can be a component of an eating disorder such as bulimia, and is itself now classified as an eating disorder on its own, purging disorder. Complications Aspiration Vomiting is dang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Corkscrew Esophagus
Diffuse esophageal spasm (DES), also known as distal esophageal spasm, is a condition characterized by uncoordinated contractions of the esophagus, which may cause difficulty swallowing (dysphagia) or regurgitation. In some cases, it may cause symptoms such as chest pain, similar to heart disease. In many cases, the cause of DES remains unknown. Certain abnormalities on x-ray imaging are commonly observed in DES, such as a "corkscrew esophagus" or "rosary bead esophagus", although these findings are not unique to this condition. Specialized testing called manometry can be performed to evaluate the motor function of the esophagus, which can help identify abnormal patterns of muscle contraction within the esophagus that are suggestive of DES. The treatment of DES consists primarily of medications, such as acid suppressing agents (like proton-pump inhibitors), calcium channel blockers, hyoscine butylbromide, or nitrates. In only extremely rare cases, surgery may be considered. Peopl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Esophageal Motility Study
An esophageal motility study (EMS) or esophageal manometry is a test to assess motor function of the upper esophageal sphincter (UES), esophageal body and lower esophageal sphincter (LES). Indications An EMS is typically done to evaluate suspected disorders of motility or peristalsis of the esophagus. These include achalasia, diffuse esophageal spasm, nutcracker esophagus and hypertensive lower esophageal sphincter. These disorders typically present with dysphagia, or difficulty swallowing, usually to both solids and liquids even initially. Other patients with spasm disorders may have the test done to diagnose chest pain thought not to be of cardiac cause. The test is not useful for anatomical disorders of the esophagus (that is, disorders that distort the anatomy of the esophagus), such as peptic strictures and esophageal cancer. Procedure A technician places a catheter into the nose and then guides it into the stomach. Once placed in the stomach lining, the catheter is slo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peristalsis
Peristalsis ( , ) is a radially symmetrical contraction and relaxation of muscles that propagate in a wave down a tube, in an anterograde direction. Peristalsis is progression of coordinated contraction of involuntary circular muscles, which is preceded by a simultaneous contraction of the longitudinal muscle and relaxation of the circular muscle in the lining of the gut. In much of a digestive tract such as the human gastrointestinal tract, smooth muscle tissue contracts in sequence to produce a peristaltic wave, which propels a ball of food (called a bolus before being transformed into chyme in the stomach) along the tract. The peristaltic movement comprises relaxation of circular smooth muscles, then their contraction behind the chewed material to keep it from moving backward, then longitudinal contraction to push it forward. Earthworms use a similar mechanism to drive their locomotion, and some modern machinery imitate this design. The word comes from New Lati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Migrating Motor Complex
Migrating motor complex, also known as migrating myoelectric complex, migratory motor complex, migratory myoelectric complex and MMC, is a pattern of electrical activity observed in the gastrointestinal tract in a regular cycle during fasting. MMC was discovered and characterized in fasting dogs in 1969 by Dr. Joseph H. Szurszewski at the Mayo Clinic. He also showed that this activity stops upon eating a meal, and suggested that it induces a motor activity that acts as a "interdigestive housekeeper" in the small intestine. These motor complexes trigger peristaltic waves, which facilitate transportation of indigestible substances such as bone, fiber, and foreign bodies from the stomach, through the small intestine, past the ileocecal sphincter, and into the colon. MMC activity varies widely across individuals and within an individual when measured on different days. The MMC occurs every 90–230 minutes during the interdigestive phase (i.e., between meals) and is responsible fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swallowing
Swallowing, sometimes called deglutition in scientific contexts, is the process in the human or animal body that allows for a substance to pass from the mouth, to the pharynx, and into the esophagus, while shutting the epiglottis. Swallowing is an important part of eating and drinking. If the process fails and the material (such as food, drink, or medicine) goes through the trachea, then choking or pulmonary aspiration can occur. In the human body the automatic temporary closing of the epiglottis is controlled by the swallowing reflex. The portion of food, drink, or other material that will move through the neck in one swallow is called a bolus. In colloquial English, the term "swallowing" is also used to describe the action of taking in a large mouthful of food without any biting, where the word gulping is more adequate. In humans Swallowing comes so easily to most people that the process rarely prompts much thought. However, from the viewpoints of physiology, of spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vasoactive Intestinal Polypeptide
Vasoactive intestinal peptide, also known as vasoactive intestinal polypeptide or VIP, is a peptide hormone that is vasoactive in the intestine. VIP is a peptide of 28 amino acid residues that belongs to a glucagon/secretin superfamily, the ligand of class II G protein–coupled receptors. VIP is produced in many tissues of vertebrates including the gut, pancreas, and suprachiasmatic nuclei of the hypothalamus in the brain. VIP stimulates contractility in the heart, causes vasodilation, increases glycogenolysis, lowers arterial blood pressure and relaxes the smooth muscle of trachea, stomach and gallbladder. In humans, the vasoactive intestinal peptide is encoded by the ''VIP'' gene. VIP has a half-life (t½) in the blood of about two minutes. Function In the body VIP has an effect on several tissues: In the digestive system, VIP seems to induce smooth muscle relaxation (lower esophageal sphincter, stomach, gallbladder), stimulate secretion of water into pancreatic juice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nitric Oxide
Nitric oxide (nitrogen oxide or nitrogen monoxide) is a colorless gas with the formula . It is one of the principal oxides of nitrogen. Nitric oxide is a free radical: it has an unpaired electron, which is sometimes denoted by a dot in its chemical formula (•N=O or •NO). Nitric oxide is also a heteronuclear diatomic molecule, a class of molecules whose study spawned early modern theories of chemical bonding. An important intermediate in industrial chemistry, nitric oxide forms in combustion systems and can be generated by lightning in thunderstorms. In mammals, including humans, nitric oxide is a signaling molecule in many physiological and pathological processes. It was proclaimed the "Molecule of the Year" in 1992. The 1998 Nobel Prize in Physiology or Medicine was awarded for discovering nitric oxide's role as a cardiovascular signalling molecule. Nitric oxide should not be confused with nitrogen dioxide (NO2), a brown gas and major air pollutant, or with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
