The urinary bladder is a muscular organ that lies in the anterior pelvic cavity and stores urine. An empty bladder has a tetrahedral shape, with an apex, base, neck, and three surfaces. It contains smooth muscle fibers that help control urine flow. The ureters open at the bladder's posterior lateral angle. Blood supply comes from branches of the internal iliac artery, and lymphatic drainage is to the vesical, external iliac, internal iliac, and common iliac lymph nodes. Nerve supply involves the sympathetic, parasympathetic, and somatic nervous systems to facilitate storage and micturition. During filling the internal sphincter contracts via sympathetic stimulation while the detr

1. ANATOMY AND PHYSIOLOGY OF
URINARY BLADDER
DR K R SHARMA

2. ANATOMY OF URINARY BLADDER

3. Introduction
• The urinary bladder is a muscular organ which
lies in the anterior part of pelvic cavity and helps in
the storage of urine.
• Shape, size and position of bladder varies according
to the amount of urine contained in it.
• An empty bladder lies entirely within the pelvis
but as it fills it extends into abdominal cavity.
• Empty bladder-tetrahedral
• Filled bladder- oval shaed

4. GROSS FEATURES
• An empty bladder is tetrahedral in shape &
has:
• 1. Apex
• 2. Base or fundus
• 3. Neck
• 4. 3 surfaces: superior, right & left
inferolateral.
• 5. 4 borders: anterior, posterior & 2 lateral
lateral borders.

6. In female: Vagina and cervix of
the uterus.

7. Neck: Inferior and most fixed part.
In male: Related to prostate.
Surrounded by smooth muscle fibres
which form preprostatic sphincter.
In female: Related to pelvic fascia.

8. Puboprostatic ligaments in male
& pubovesical ligaments in
female.

10. • The ureters open at the
posterolateral angle of the trigone.
• Uvula vesicae: It is a small
elevation on the trigone posterior
to the urethral orifice produced by
median lobe of prostate.

15. BLOOD SUPPLY OF URINARY BLADDER
• ARTERIAL-
- superior,
middle, and
inferior vesicle artery
branch of ant. trunk of internal iliac artery
-banches from obturator and inferior gluteal
artery
In females- uterine and vaginal artery also send
branches

16. Venous and lymphatics drainage
• Venous
Surrounding the bladder is a rich plexus of veins
that ultimately empties into internal iliac veins
lymhatics- drain into
-vesical
-external iliac
-internal iliac
-common iliac lymph node

17. PHYSIOLOGY OF URINARY BLADDER

18. NERVE SUPPLY
• SYMPATHETIC: CENTRE: T11-L2
SUPPLY THROUGH: • SYMPATHETIC CHAIN
GANGLIA-PREVERTEBRAL GANGLIA-HYPOGASTRIC
AND PELVIC PLEXUS – INFERIOR MESENTRIC
GANGLION –POST GANGLIONIC FIBRES FUNCTION:
• VIA Β3-ADRENERGIC RECEPTORS -INHIBITION
AND RELAXATION OF THE DETRUSSOR MUSCLE.
• VIA ALPHA1 RECEPTORS CAUSES CONTRACTION OF
INTERNAL SPHINCTER
• FACILITATE BLADDER STORAGE AND CONTINENCE

19. Conti..
PARASYMPATHETIC:
• • CENTRE: S2-S4
• • SUPPLY THROUGH: PELVIC SPLANCHNIC NERVES
• END IN : GANGLIA IN BLADDER WALL •
NEUROTRANSMITTER : ACH VIA M2, M3 •
FUNCTION: CHOLINERGIC TRANSMISSION IS THE
MAJOR EXCITATORY MECHANISM • M2 AND M3
ON DETRUSSOR SMOOTH MUSCLE INITIATES
BLADDER DETRUSSOR CONTRACTION
• AND INTERNAL SPHINCTER RELAXATION VIA
NITRIC OXIDE

20. SOMATIC :
• CENTRE: ONUF’S NUCLEUS S2-S4
• SUPPLY THROUGH: PUDENDAL
NERVES
• FUNCTION : CONTROLS THE
EXTERNAL SPHINCTER

22. Cortical and brain stem centre
• Cortical centre- 2nd frontal gyrus paracentral
lobule
- inhibitory to pontine centre
Brain stem centre- barrington nucleus
-coordinating centre
- facilitatory to micturition
-synchronization and maintanance of
sustained contraction to complete evacuation

23. filling
• Sympathetic stimulated-internal sphinctor
contracted
• Parasympathetic inhibited- detruser relaxed

24. voiding
• Afferent from bladder
mucosa –pain, touch, temprature
detruser ms and lamina propria –strech
receptor
these afferent passes via inferior
hypogastric plexus
Then spinal micturition reflex comes in play
controlled by higher centres.

25. THANK YOU ….