The long, narrow duct that conveys urine from the kidney to the urinary bladder or cloaca.
[New Latin ūrētēr, from Greek ourētēr, from ourein, to urinate.]
ureteral u·re'ter·al or u're·ter'ic (yʊr'ĭ-tĕr'ĭk) adj.
ureter
Dictionary:
u·re·ter (yʊ-rē'tər, yʊr'ĭ-tər)  |
n.
| World of the Body: ureter |
The tube of smooth muscle which carries urine from the kidney to the bladder. The ureter starts as the outlet from the ‘pelvis’ in the centre of the kidney — the receptacle for the urine leaving thousands of microscopic tubules. The two ureters enter the upper part of the bladder symmetrically on the two sides. Between them, they deliver urine on average at a rate of about 1 ml min. The ureters can be a source of pain (colic) if kidney stones fragment and pass down them.
— Stuart Judge
See kidneys; urogenital system.
| Columbia Encyclopedia: ureter |
ureter (yʊrē'tər), thick-walled tube that conveys urine from the kidney to the urinary bladder. It is approximately 10 in. (25.4 cm) long, with the upper half located in the abdomen and the lower half in the pelvic region. Urine is transported down this tube under the impetus of gravity assisted by contractions of the smooth muscles that line the ureteral walls. A blocked ureter can result from congenital abnormality, a tumor, or the formation of kidney stones. Blockage may require surgery to prevent loss of urinary function and eventual urea poisoning. See urinary system.
| Health Dictionary: ureters |
(yoor-uh-tuhrz, yoo-ree-tuhrz)
The tubes that carry urine from each kidney to the urinary bladder.
| Veterinary Dictionary: ureteral |
Pertaining to or emanating from the ureter.
- u. calculus — ureterolith.
- u. distention — ureterectasis.
- u. duplication — a rare anomaly in animals in which there is more than one ureter from a kidney.
- u. ectopia — see ectopic ureter.
- u. hypoplasia — usually segmental underdevelopment of the ureter causing stenosis and hydronephrosis.
- u. obstruction — may be caused by intraluminal lesions, e.g. urolithiasis, or as part of pyelonephritis or by external compression of the ureter or as a congenital defect. Sudden blockage causes acute abdominal pain that lasts for several hours. Subsequently or if obstruction develops slowly the kidney on the affected side becomes hydronephrotic; if bilateral, renal failure follows.
- u. reflux — see vesicoureteral reflux.
- u. rupture — rupture usually results from trauma; leads to urinoma or peritoneal accumulation of urine.
- u. stasis — synonymous with obstruction.
- u. valves — a rare anomaly that may be a cause of urinary incontinence.
| Wikipedia: Ureter |
| Ureter | |||
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| Gray's | subject #254 1225 | ||
| Artery | Superior vesical artery, Vaginal artery, Ureteral branches of renal artery | ||
| Precursor | Ureteric bud | ||
| MeSH | Ureter | ||
| Dorlands/Elsevier | Ureter | ||
In human anatomy, the ureters are muscular tube that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually 25–30 cm (10–12 in) long and ~3-4 mm in diameter.
In humans, the ureters arise from the renal pelvis on the medial aspect of each kidney before descending towards the bladder on the front of the psoas major muscle. The ureters cross the pelvic brim near the bifurcation of the iliac arteries (which they run over). This "pelviureteric junction" is a common site for the impaction of kidney stones (the other being the ureterovesical valve). The ureters run posteroinferiorly on the lateral walls of the pelvis They then curve anteriormedially to enter the bladder through the back, at the vesicoureteric junction, running within the wall of the bladder for a few centimeters. The backflow of urine is prevented by valves known as ureterovesical valves.
In the female, the ureters pass through the mesometrium on the way to the urinary bladder.
Ureters are also found in all other amniote species, although different ducts fulfil the same role in amphibians and fish.[1]
Contents |
Histology
The ureteric lumen is star-shaped. Like the bladder, it is lined with transitional epithelium, and contains layers of smooth muscle, thereby being under autonomic control.
The epithelial cells of the ureter are stratified (in many layers), are normally round in shape but become squamous (flat) when stretched. The lamina propria is thick and elastic (as it is important that it is impermeable).
There are two spiral layers of smooth muscle in the ureter wall, an inner loose spiral, and an outer tight spiral. The inner loose spiral is sometimes described as longitudinal, and the outer as circular, (this is the opposite to the situation in the gastrointestinal tract). The distal third of the ureter contains another layer of outer longitudinal muscle.
The adventitia of the ureter, like elsewhere is composed of fibrous connective tissue, that binds it to adjacent tissues.
References
- ^ Romer, Alfred Sherwood; Parsons, Thomas S. (1977). The Vertebrate Body. Philadelphia, PA: Holt-Saunders International. p. 378. ISBN 0-03-910284-X.
External links
- SUNY Labs 40:06-0111 - "Posterior Abdominal Wall: Internal Structure of a Kidney"
- SUNY Figs 43:08-02 - "Relationship of the ureter to the uterine artery."
- SUNY Figs 44:02-01 - "Mid-sagittal section of male pelvis."
- SUNY Anatomy Image 8923
- SUNY Anatomy Image 8945
- Virtual Slidebox at Univ. Iowa Slide 444
- Organology at UC Davis Urinary/mammal/ureter/ureter1 - "Mammal, ureter (LM, Medium)"
- Histology at KUMC urinary-renal15 - "Ureter"
- Cross section at UV pelvis/pelvis-female-17
Additional images
 Bladder |
 Frontal section through the kidney |
 Wall of the ureter. |
 Transverse section of human embryo eight and a half to nine weeks old. |
 Tail end of human embryo thirty-two to thirty-three days old. |
 The relations of the viscera and large vessels of the abdomen. (Seen from behind, the last thoracic vertebra being well raised.) |
 The posterior surfaces of the kidneys, showing areas of relation to the parietes. |
 Vertical section of kidney. |
 Transverse section of ureter. |
 The interior of bladder. |
 Fundus of the bladder with the vesiculæ seminales. |
 Median sagittal section of male pelvis. |
 Microscopic view of dog ureter. |
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 | Dictionary. The American Heritage® Dictionary of the English Language, Fourth Edition Copyright © 2007, 2000 by Houghton Mifflin Company. Updated in 2009. Published by Houghton Mifflin Company. All rights reserved. Read more |
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| World of the Body. The Oxford Companion to the Body. Copyright © 2001, 2003 by Oxford University Press. All rights reserved. Read more |
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| Columbia Encyclopedia. The Columbia Electronic Encyclopedia, Sixth Edition Copyright © 2003, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/. Read more |
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| Health Dictionary. The New Dictionary of Cultural Literacy, Third Edition Edited by E.D. Hirsch, Jr., Joseph F. Kett, and James Trefil. Copyright © 2002 by Houghton Mifflin Company. Published by Houghton Mifflin. All rights reserved. Read more |
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| Veterinary Dictionary. Saunders Comprehensive Veterinary Dictionary 3rd Edition. Copyright © 2007 by D.C. Blood, V.P. Studdert and C.C. Gay, Elsevier. All rights reserved. Read more |
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| Wikipedia. This article is licensed under the Creative Commons Attribution/Share-Alike License. It uses material from the Wikipedia article "Ureter". Read more |
