Urinary bladder

Jump to: navigation, search
Urinary bladder
Illu urinary system.jpg
Urinary system.
Illu bladder.jpg
Bladder
Latin vesica urinaria
Gray's subject #255 1227
Artery Superior vesical artery
Inferior vesical artery
Umbilical artery
Vaginal artery
Vein Vesical venous plexus
Nerve Vesical nervous plexus
Lymph external iliac lymph nodes, internal iliac lymph nodes
Precursor urogenital sinus
MeSH Bladder
Dorlands/Elsevier v_07/12855244

WikiDoc Resources for Urinary bladder

Articles

Most recent articles on Urinary bladder

Most cited articles on Urinary bladder

Review articles on Urinary bladder

Articles on Urinary bladder in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Urinary bladder

Images of Urinary bladder

Photos of Urinary bladder

Podcasts & MP3s on Urinary bladder

Videos on Urinary bladder

Evidence Based Medicine

Cochrane Collaboration on Urinary bladder

Bandolier on Urinary bladder

TRIP on Urinary bladder

Clinical Trials

Ongoing Trials on Urinary bladder at Clinical Trials.gov

Trial results on Urinary bladder

Clinical Trials on Urinary bladder at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Urinary bladder

NICE Guidance on Urinary bladder

NHS PRODIGY Guidance

FDA on Urinary bladder

CDC on Urinary bladder

Books

Books on Urinary bladder

News

Urinary bladder in the news

Be alerted to news on Urinary bladder

News trends on Urinary bladder

Commentary

Blogs on Urinary bladder

Definitions

Definitions of Urinary bladder

Patient Resources / Community

Patient resources on Urinary bladder

Discussion groups on Urinary bladder

Patient Handouts on Urinary bladder

Directions to Hospitals Treating Urinary bladder

Risk calculators and risk factors for Urinary bladder

Healthcare Provider Resources

Symptoms of Urinary bladder

Causes & Risk Factors for Urinary bladder

Diagnostic studies for Urinary bladder

Treatment of Urinary bladder

Continuing Medical Education (CME)

CME Programs on Urinary bladder

International

Urinary bladder en Espanol

Urinary bladder en Francais

Business

Urinary bladder in the Marketplace

Patents on Urinary bladder

Experimental / Informatics

List of terms related to Urinary bladder

Steven C. Campbell, M.D., Ph.D.


Overview

In anatomy, the urinary bladder is a hollow, muscular, and distensible (or elastic) organ that sits on the pelvic floor in mammals. It is the organ that collects urine excreted by the kidneys prior to disposal by urination. Urine enters the bladder via the ureters and exits via the urethra.

In males, the bladder is superior to the prostate, and separated from the rectum by the rectovesical excavation.

In females, the bladder is separated from the rectum by the rectouterine excavation, and it is separated from the uterus by the vesicouterine excavation.

Regions

  • Trigone of urinary bladder: The ureters enter the bladder diagonally from its dorsolateral floor in an area called the trigone, which is a triangular shaped area on the postero-inferior wall of the bladder. The urethra exits at the lowest point of the triangle of the trigone.
  • Apex: The Median umbilical ligament connects to the apex of the bladder.
  • Neck: The Neck is connected to the pubic bone by the pubovesical ligament in women, and by the puboprostatic ligament in men.

Wall

The wall of the urinary bladder consists of three layers:

Detrusor muscle

The detrusor muscle is a layer of the urinary bladder wall made of smooth muscle fibers arranged in spiral, longitudinal, and circular bundles. When the bladder is stretched, this signals the parasympathetic nervous system to contract the detrusor muscle. This encourages the bladder to expel urine through the urethra.

For the urine to exit the bladder, both the autonomically controlled internal sphincter and the voluntarily controlled external sphincter must be opened. Problems with these muscles can lead to incontinence.

The urinary bladder usually holds 400–620 mL of urine, but it can hold twice this without rupturing if, for example, the outflow is obstructed.

The desire to urinate usually starts when the bladder reaches around 75% of its working volume. If the subject is distracted the desire can fade and return with more urgency as the bladder continues to fill.

See also

External links

Additional images

bg:Пикочен мехур cs:Močový měchýř cy:Pledren da:Urinblære de:Harnblase id:Kandung kemih he:שלפוחית השתן it:Vescica urinaria lt:Šlapimo pūslė nl:Urineblaas no:Urinblære sk:Močový mechúr fi:Virtsarakko sv:Urinblåsa yi:בלעדער



Linked-in.jpg