Ureter

Ureter

Infobox Anatomy
Name = PAGENAME
Latin =
GraySubject = 254
GrayPage = 1225



Caption2 =
1. Renal pyramid
2. Efferent artery
3. Renal artery
4. Renal vein
5. Renal hilum
6. Renal pelvis
7.
Ureter
8. Minor calyx
9. Renal capsule
10. Inferior renal capsule
11. Superior renal
capsule

12. Afferent vein
13. Nephron
14. Minor calyx
15. Major calyx
16. Renal papilla
17. Renal column

Precursor = Ureteric bud
System =
Artery = Superior vesical artery, Vaginal artery, Ureteral branches of renal artery
Vein =
Nerve =
Lymph =
MeshName = Ureter
MeshNumber = A05.810.776
DorlandsPre = u_03
DorlandsSuf = 12838140
In human anatomy, the ureters are muscular ducts that propel urine from the kidneys to the urinary bladder. In the adult, the ureters are usually 25-30 cm (10-12 inches) long.

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, pressure from the filling of the bladder, and the tone of the muscle in the bladder wall.

In the female, the ureters pass through the mesometrium on the way to the urinary bladder.

Histology

The ureter has a diameter of about 3 millimeters, and the 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.

Diseases and disorders

Medical problems that can affect the ureter include:
* cancer of the ureter
* passage of kidney stones - especially at the uteropelvic junctions, where they cross the iliac vessels and their entrance to the bladder.
* ureterocele
* megaureter
* vesico-ureteric reflux
* anatomical abnormalities, such as duplexing and ectopia.

External links

* - "Posterior Abdominal Wall: Internal Structure of a Kidney"
* - "Relationship of the ureter to the uterine artery."
* - "Mid-sagittal section of male pelvis."
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*
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* - "Mammal, ureter (LM, Medium)"
* - "Ureter"
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=Additional


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Look at other dictionaries:

  • uréter — m. anat. Conducto fibrosomuscular que se extiende desde la pelvis renal hasta la vejiga y por donde se excreta la orina. Medical Dictionary. 2011. uréter …   Diccionario médico

  • ureter — URETÉR, uretere, s.n. Fiecare dintre cele două canale cilindrice subţiri, membranoase, care unesc bazinetul cu vezica urinară. – Din fr. uretère. Trimis de valeriu, 13.09.2007. Sursa: DEX 98  uretér s. n., pl. uretére Trimis de siveco,… …   Dicționar Român

  • urétér- — ⇒URÉTÉR(O) , (URÉTÉR , URÉTÉRO )élém. formant Élém. tiré du gr. « uretère », entrant dans la constr. de termes de méd.; le 2e élém. est gén. un élém. formant tiré du gr. V. urétéral (rem. s.v. uretère), urétérite (dér. s.v. uretère) et aussi:… …   Encyclopédie Universelle

  • ureter(o)- — [ureter, q.v.] a combining form denoting relationship to the ureter …   Medical dictionary

  • ureter — 1570s, from medical L. ureter, from Gk. oureter, from ourein to urinate, from ouron (see URINE (Cf. urine)) …   Etymology dictionary

  • ureter — s. m. [Anatomia] Cada um dos canais que conduzem a urina dos rins para a bexiga.   ♦ Grafia em Portugal: uréter …   Dicionário da Língua Portuguesa

  • uréter — s. m. [Anatomia] Cada um dos canais que conduzem a urina dos rins para a bexiga. • [Portugal] Plural: ureteres.   ♦ Grafia no Brasil: ureter …   Dicionário da Língua Portuguesa

  • Ureter — U*re ter (?; 277), n. [NL., fr. Gr. ?. See {Urine}.] (Anat.) The duct which conveys the urine from the kidney to the bladder or cloaca. There are two ureters, one for each kidney. [1913 Webster] …   The Collaborative International Dictionary of English

  • Urēter — (gr), Harnleiter. Daher ureteralgie, Schmerz in den Harnleitern. Ureterische Arterien (Arteriae uretericae), aus den Nieren , Samen , hypogastrischen Arterien, auch wohl aus der Aorta an die Harnleiter gehende Arterienzweige Ureterische Nerven… …   Pierer's Universal-Lexikon

  • Urēter — (lat.), Harnleiter, s. Nieren …   Meyers Großes Konversations-Lexikon

  • Ureter — Urēter (grch.), der Harnleiter, in dem der Urin von der Niere in die Blase gelangt; Ureterītis, Harnleiterentzündung; Ureterotomīe, die operative Eröffnung des Harnleiters behufs Steinextraktion …   Kleines Konversations-Lexikon

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