The physiologic or functional barrier to GASTROESOPHAGEAL REFLUX at the esophagogastric junction. Sphincteric muscles remain tonically contracted during the resting state and form the high-pressure zone separating the lumen of the ESOPHAGUS from that of the STOMACH. (Haubrich et al, Bockus Gastroenterology, 5th ed., pp399, 415)

The structure at the pharyngoesophageal junction consisting chiefly of the CRICOPHARYNGEUS MUSCLE. It normally occludes the lumen of the ESOPHAGUS, except during SWALLOWING.

The area covering the terminal portion of ESOPHAGUS and the beginning of STOMACH at the cardiac orifice.

Measurement of the pressure or tension of liquids or gases with a manometer.

The act of taking solids and liquids into the GASTROINTESTINAL TRACT through the mouth and throat.

The sphincter of the hepatopancreatic ampulla within the duodenal papilla. The COMMON BILE DUCT and main pancreatic duct pass through this sphincter.

The muscular membranous segment between the PHARYNX and the STOMACH in the UPPER GASTROINTESTINAL TRACT.

A movement, caused by sequential muscle contraction, that pushes the contents of the intestines or other tubular organs in one direction.

A type of stress exerted uniformly in all directions. Its measure is the force exerted per unit area. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

A motility disorder of the ESOPHAGUS in which the LOWER ESOPHAGEAL SPHINCTER (near the CARDIA) fails to relax resulting in functional obstruction of the esophagus, and DYSPHAGIA. Achalasia is characterized by a grossly contorted and dilated esophagus (megaesophagus).

Retrograde flow of gastric juice (GASTRIC ACID) and/or duodenal contents (BILE ACIDS; PANCREATIC JUICE) into the distal ESOPHAGUS, commonly due to incompetence of the LOWER ESOPHAGEAL SPHINCTER.

New World marsupials of the family Didelphidae. Opossums are omnivorous, largely nocturnal and arboreal MAMMALS, grow to about three feet in length, including the scaly prehensile tail, and have an abdominal pouch in which the young are carried at birth.

Difficulty in SWALLOWING which may result from neuromuscular disorder or mechanical obstruction. Dysphagia is classified into two distinct types: oropharyngeal dysphagia due to malfunction of the PHARYNX and UPPER ESOPHAGEAL SPHINCTER; and esophageal dysphagia due to malfunction of the ESOPHAGUS.

That phase of a muscle twitch during which a muscle returns to a resting position.

The terminal segment of the LARGE INTESTINE, beginning from the ampulla of the RECTUM and ending at the anus.

Analysis of the HYDROGEN ION CONCENTRATION in the lumen of the ESOPHAGUS. It is used to record the pattern, frequency, and duration of GASTROESOPHAGEAL REFLUX.

Disorders affecting the motor function of the UPPER ESOPHAGEAL SPHINCTER; LOWER ESOPHAGEAL SPHINCTER; the ESOPHAGUS body, or a combination of these parts. The failure of the sphincters to maintain a tonic pressure may result in gastric reflux of food and acid into the esophagus (GASTROESOPHAGEAL REFLUX). Other disorders include hypermotility (spastic disorders) and markedly increased amplitude in contraction (nutcracker esophagus).

INFLAMMATION, acute or chronic, of the ESOPHAGUS caused by BACTERIA, chemicals, or TRAUMA.

The small thick cartilage that forms the lower and posterior parts of the laryngeal wall.

The muscles of the PHARYNX are voluntary muscles arranged in two layers. The external circular layer consists of three constrictors (superior, middle, and inferior). The internal longitudinal layer consists of the palatopharyngeus, the salpingopharyngeus, and the stylopharyngeus. During swallowing, the outer layer constricts the pharyngeal wall and the inner layer elevates pharynx and LARYNX.

Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)

A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.

The state of activity or tension of a muscle beyond that related to its physical properties, that is, its active resistance to stretch. In skeletal muscle, tonus is dependent upon efferent innervation. (Stedman, 25th ed)

A funnel-shaped fibromuscular tube that conducts food to the ESOPHAGUS, and air to the LARYNX and LUNGS. It is located posterior to the NASAL CAVITY; ORAL CAVITY; and LARYNX, and extends from the SKULL BASE to the inferior border of the CRICOID CARTILAGE anteriorly and to the inferior border of the C6 vertebra posteriorly. It is divided into the NASOPHARYNX; OROPHARYNX; and HYPOPHARYNX (laryngopharynx).

Endoscopic examination, therapy or surgery of the esophagus.

Mobilization of the lower end of the esophagus and plication of the fundus of the stomach around it (fundic wrapping) in the treatment of GASTROESOPHAGEAL REFLUX that may be associated with various disorders, such as hiatal hernia. (From Dorland, 28th ed)

Pathological processes in the ESOPHAGUS.

The striated muscle groups which move the LARYNX as a whole or its parts, such as altering tension of the VOCAL CORDS, or size of the slit (RIMA GLOTTIDIS).

Production of an image when x-rays strike a fluorescent screen.

STOMACH herniation located at or near the diaphragmatic opening for the ESOPHAGUS, the esophageal hiatus.

An organ of digestion situated in the left upper quadrant of the abdomen between the termination of the ESOPHAGUS and the beginning of the DUODENUM.

Saccular protrusion beyond the wall of the ESOPHAGUS.

A genus of large OPOSSUMS in the family Didelphidae, found in the Americas. The species Didelphis virginiana is prominent in North America.

Organic or functional motility disorder involving the SPHINCTER OF ODDI and associated with biliary COLIC. Pathological changes are most often seen in the COMMON BILE DUCT sphincter, and less commonly the PANCREATIC DUCT sphincter.

The motor activity of the GASTROINTESTINAL TRACT.

A peptide of about 22-amino acids isolated from the DUODENUM. At low pH it inhibits gastric motor activity, whereas at high pH it has a stimulating effect.

An alkaloid, originally from Atropa belladonna, but found in other plants, mainly SOLANACEAE. Hyoscyamine is the 3(S)-endo isomer of atropine.

INFLAMMATION of the ESOPHAGUS that is caused by the reflux of GASTRIC JUICE with contents of the STOMACH and DUODENUM.

Failure of voluntary control of the anal sphincters, with involuntary passage of feces and flatus.

A stricture of the ESOPHAGUS. Most are acquired but can be congenital.

A family of gastrointestinal peptide hormones that excite the secretion of GASTRIC JUICE. They may also occur in the central nervous system where they are presumed to be neurotransmitters.

An artifical implanted device, usually in the form of an inflatable silicone cuff, inserted in or around the bladder neck in the surgical treatment of urinary incontinence caused by sphincter weakness. Often it is placed around the bulbous urethra in adult males. The artificial urinary sphincter is considered an alternative to urinary diversion.

The domestic cat, Felis catus, of the carnivore family FELIDAE, comprising over 30 different breeds. The domestic cat is descended primarily from the wild cat of Africa and extreme southwestern Asia. Though probably present in towns in Palestine as long ago as 7000 years, actual domestication occurred in Egypt about 4000 years ago. (From Walker's Mammals of the World, 6th ed, p801)

Use or insertion of a tubular device into a duct, blood vessel, hollow organ, or body cavity for injecting or withdrawing fluids for diagnostic or therapeutic purposes. It differs from INTUBATION in that the tube here is used to restore or maintain patency in obstructions.

The ejection of gas or air through the mouth from the stomach.

The act of dilating.

A slowly hydrolyzing muscarinic agonist with no nicotinic effects. Bethanechol is generally used to increase smooth muscle tone, as in the GI tract following abdominal surgery or in urinary retention in the absence of obstruction. It may cause hypotension, HEART RATE changes, and BRONCHIAL SPASM.

A group of compounds that are derivatives of beta-methylacetylcholine (methacholine).

Drugs used in the treatment of movement disorders. Most of these act centrally on dopaminergic or cholinergic systems. Among the most important clinically are those used for the treatment of Parkinson disease (ANTIPARKINSON AGENTS) and those for the tardive dyskinesias.

Compounds containing the hexamethylenebis(trimethylammonium) cation. Members of this group frequently act as antihypertensive agents and selective ganglionic blocking agents.

A tube that transports URINE from the URINARY BLADDER to the outside of the body in both the sexes. It also has a reproductive function in the male by providing a passage for SPERM.

A nonselective alpha-adrenergic antagonist. It is used in the treatment of hypertension and hypertensive emergencies, pheochromocytoma, vasospasm of RAYNAUD DISEASE and frostbite, clonidine withdrawal syndrome, impotence, and peripheral vascular disease.

A strong corrosive acid that is commonly used as a laboratory reagent. It is formed by dissolving hydrogen chloride in water. GASTRIC ACID is the hydrochloric acid component of GASTRIC JUICE.

The 10th cranial nerve. The vagus is a mixed nerve which contains somatic afferents (from skin in back of the ear and the external auditory meatus), visceral afferents (from the pharynx, larynx, thorax, and abdomen), parasympathetic efferents (to the thorax and abdomen), and efferents to striated muscle (of the larynx and pharynx).

A condition with damage to the lining of the lower ESOPHAGUS resulting from chronic acid reflux (ESOPHAGITIS, REFLUX). Through the process of metaplasia, the squamous cells are replaced by a columnar epithelium with cells resembling those of the INTESTINE or the salmon-pink mucosa of the STOMACH. Barrett's columnar epithelium is a marker for severe reflux and precursor to ADENOCARCINOMA of the esophagus.

An involuntary movement or exercise of function in a part, excited in response to a stimulus applied to the periphery and transmitted to the brain or spinal cord.

Endoscopic examination, therapy or surgery of the gastrointestinal tract.

Use of electric potential or currents to elicit biological responses.

A widely used non-cardioselective beta-adrenergic antagonist. Propranolol has been used for MYOCARDIAL INFARCTION; ARRHYTHMIA; ANGINA PECTORIS; HYPERTENSION; HYPERTHYROIDISM; MIGRAINE; PHEOCHROMOCYTOMA; and ANXIETY but adverse effects instigate replacement by newer drugs.

A peptide hormone of about 27 amino acids from the duodenal mucosa that activates pancreatic secretion and lowers the blood sugar level. (USAN and the USP Dictionary of Drug Names, 1994, p597)

The most anterior portion of the uveal layer, separating the anterior chamber from the posterior. It consists of two layers - the stroma and the pigmented epithelium. Color of the iris depends on the amount of melanin in the stroma on reflection from the pigmented epithelium.

Diseases of the COMMON BILE DUCT including the AMPULLA OF VATER and the SPHINCTER OF ODDI.

The domestic dog, Canis familiaris, comprising about 400 breeds, of the carnivore family CANIDAE. They are worldwide in distribution and live in association with people. (Walker's Mammals of the World, 5th ed, p1065)

A GAMMA-AMINOBUTYRIC ACID derivative that is a specific agonist of GABA-B RECEPTORS. It is used in the treatment of MUSCLE SPASTICITY, especially that due to SPINAL CORD INJURIES. Its therapeutic effects result from actions at spinal and supraspinal sites, generally the reduction of excitatory transmission.

The storing or preserving of video signals for television to be played back later via a transmitter or receiver. Recordings may be made on magnetic tape or discs (VIDEODISC RECORDING).

The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH = log 1/2[1/(H+)], where (H+) is the hydrogen ion concentration in gram equivalents per liter of solution. (McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)

A procedure in which a laparoscope (LAPAROSCOPES) is inserted through a small incision near the navel to examine the abdominal and pelvic organs in the PERITONEAL CAVITY. If appropriate, biopsy or surgery can be performed during laparoscopy.

A dilation of the duodenal papilla that is the opening of the juncture of the COMMON BILE DUCT and the MAIN PANCREATIC DUCT, also known as the hepatopancreatic ampulla.

Torn, ragged, mangled wounds.

A neurotransmitter found at neuromuscular junctions, autonomic ganglia, parasympathetic effector junctions, a subset of sympathetic effector junctions, and at many sites in the central nervous system.

'Anus diseases' refer to various medical conditions affecting the anus, including structural abnormalities, inflammatory disorders, infections, and neoplasms, which can cause symptoms such as pain, bleeding, itching, or changes in bowel habits.

The distal segment of the LARGE INTESTINE, between the SIGMOID COLON and the ANAL CANAL.

The mechanical laws of fluid dynamics as they apply to urine transport.

A painful linear ulcer at the margin of the anus. It appears as a crack or slit in the mucous membrane of the anus and is very painful and difficult to heal. (Dorland, 27th ed & Stedman, 25th ed)

A free radical gas produced endogenously by a variety of mammalian cells, synthesized from ARGININE by NITRIC OXIDE SYNTHASE. Nitric oxide is one of the ENDOTHELIUM-DEPENDENT RELAXING FACTORS released by the vascular endothelium and mediates VASODILATION. It also inhibits platelet aggregation, induces disaggregation of aggregated platelets, and inhibits platelet adhesion to the vascular endothelium. Nitric oxide activates cytosolic GUANYLATE CYCLASE and thus elevates intracellular levels of CYCLIC GMP.