Urinary bladder

From WikiMD's Wellnesspedia

The urinary bladder is a hollow, muscular organ that collects and stores urine produced by the kidneys before its eventual excretion. Located in the pelvis, just posterior to the pubic bone, the bladder plays a central role in the body's urinary system.

Urinary bladder

Anatomy[edit | edit source]

The bladder's anatomy allows it to store and expel urine:

  • Mucosa: The innermost layer, lined with transitional epithelium that can stretch as the bladder fills.
  • Muscularis: A layer of smooth muscle known as the detrusor muscle, which contracts to expel urine.
  • Adventitia: The outermost layer, made of connective tissue.

The bladder's shape is akin to an inverted pyramid, with its apex pointing forward and downward.

Function[edit | edit source]

The primary function of the urinary bladder is to store urine until a person decides to void:

  • Storage: The bladder can typically hold about 400-600 ml of urine.
  • Voiding: Through a process called micturition, where the detrusor muscle contracts and the internal urethral sphincter relaxes, allowing urine to flow into the urethra.

Physiology[edit | edit source]

The filling and emptying of the bladder are regulated by a complex interplay of the:

  • Central Nervous System: The brain recognizes bladder distension and can control the timing of micturition.
  • Autonomic Nervous System: Especially the parasympathetic and sympathetic divisions, which control involuntary bladder contractions and relaxation of the sphincters.
  • Somatic Nervous System: Helps control the external urethral sphincter, providing voluntary control over voiding.

Disorders[edit | edit source]

Various disorders can affect the urinary bladder:

Diagnosis and Treatment[edit | edit source]

Diagnosis of bladder conditions often involves:

  • Urinalysis: Examination of urine for signs of infection, blood, or cancer cells.
  • Cystoscopy: Using a thin camera to inspect the inside of the bladder.
  • Imaging: Like Ultrasound or CT scans to visualize the bladder and surrounding organs.

Treatment depends on the specific condition:

  • Antibiotics: For infections.
  • Surgery: To remove tumors or stones.
  • Bladder training: For overactive bladder, teaching individuals to resist the urge to void and gradually increase the intervals between emptying the bladder.



Wiki.png

Navigation: Wellness - Encyclopedia - Health topics - Disease Index‏‎ - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes

Search WikiMD


Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro) available.
Advertise on WikiMD

WikiMD is not a substitute for professional medical advice. See full disclaimer.

Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.


Contributors: Prab R. Tumpati, MD