In the name of God

Anatomy:

Genitourinary System

Moradian MD, MPH, PhD Candidate

Tehran University of Medical Sciences

drmoradian@sums.ac.ir

2013Dr. Budgie

Hussain

Pearson, Inc.,

Pearson Benjamin

Cummings 2009

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عملکردهای اصلی دستگاه ادراری

:تسدایىذ‏آن‏از‏را‏زیر‏مًاد‏تا‏کىىذ‏می‏فیلتر‏را‏خًن‏َا‏کلیٍ‏زیادی‏آب‏ساز،‏ي‏سًخت‏ديرریختىی‏محصًلات‏،‏سمًمتذن‏زیادی‏یًوُای‏ي‏تذن‏ي‏ايریک‏اسیذ‏ايرٌ،‏:مثل‏ویتريشن‏حايی‏ریختىی‏دير‏مًارد

کراتیىیه‏حفظ‏را‏تذن‏تاز-اسیذ‏سطح‏ي‏تذن‏َای‏الکتريلیت‏آب،‏تعادل

(رویه)‏کىذ‏می‏است‏استخًان‏مغس‏در‏سازی‏خًن‏محرک‏کٍ‏را‏اریتريپًئتیه

.کىىذ‏می‏ترشح‏را

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Main Functions of Urinary SystemKidneys filter blood to keep it pure

Toxins

Metabolic wastes

Excess water

Excess ions

Dispose of nitrogenous wastes from blood Urea

Uric acid

Creatinine

Regulate the balance of water and electrolytes, acids and bases (Renin)

Secrete Erythtopoetine that stimulate BM RBC production

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The Urinary System

Paired kidneysکلیٍ‏َا‏‏‏

A Ureter for each kidney

حالة-میسوای

Urinary bladder

مثاوٍ‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏

Urethra پیشاتراٌ

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Kidneys are retroperitoneal organs خلف صفاق superior lumbar region of posterior abdominal wall

Hilus is cleft: vessels, ureters and nerves enter and leave واف

Adrenal glands lie superior to each kidney ًغدد فوق کلی

11 cm , 130-150 gr

*

*

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Kidneys layers

renal medulla منطقه مرکزی کلیه ها

renal cortex منطقه قشری کلیه ها

renal capsule کپسول لیفی

perinephric (perirenal) fat کپسول چربی

renal fascia نیام کلیه

paranephric (pararenal) fat چربی پارارنال

peritoneum (anteriorly), and transversalis

fascia (posteriorly)7

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Transverse sections show

retroperitoneal position of

kidneys

Note also: liver, aorta

muscles on CT

Note layers of adipose

(fat), capsule, fascia

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Kidney regionsCortex: outer

Columns of cortex divide medulla into “pyramids”

Medulla: innerDarker, cone-shaped medullary or renal pyramids

Parallel bundles of urine-collecting tubules

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The human kidney has lobesPyramid and cortical tissue surrounding it

5-11 per kidney

Renal pelvis (=basin)Expanded, funnel shaped, superior part ofureters

Branches to form two or three major calices

Each of these divides again, minor calices:collect urine from papillae of pyramids

Kidney Structure

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Kidney Structure

Nephron وفرون : واحد ساختماوی کلیً

Renal corpuscle (in cortex) ًجسمک کلی

Glomerulus (tuft of capillaries) گلومرول

Glomerular (Bowman’s) capsule کپسول بومه

Tubular sectionProximal convoluted tubule لولً پیچیدي وسدیک

Loop of Henle ًقوش ٌىل

Distal convoluted tubule لولً پیچیدي دور

Collecting duct مجرای جمع کىىدي

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Nephron

A. Renal Vein

B. Renal Artery

C. Ureter

D. Medulla

E. Renal Pelvis

F. Cortex

1. Ascending loop of

Henle

2. Descending loop of

Henle

3. Peritubular

capillaries

4. Proximal tubule

5. Glomerulus

6. Distal tubule

The Kidney and the Nephron

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More than a million of these tubules act

together to form the urine

Three main mechanisms

a. Glomerular filtration

b. Tubular reabsorption

c. Tubular secretion

Two major parts

1. A urine-forming nephron

2. A collecting duct which

concentrates urine by removing

water from it

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Scanning EM of podocytes clinging to

capillaries (left) and filtration membrane

diagram (right) The capillary pores (fenestrations)

restrict the passage of the largest

elements such as blood cells

The basement membrane and slit

diaphragm hold back all but the smallest

proteins while letting through small

molecules such as water, ions, glucose,

amino acids, and urea

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Classes of

nephrons

• Cortical nephrons– 85% of all

nephrons

– Almost entirely within cortex

• Juxtamedullarynephrons– Renal corpuscles

near cortex-medulla junction

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The collecting ducts

• The most important role is to conserve bodyfluids

• When the body must conserve water, theposterior pituitary gland secretes ADH(antidiuretic hormone)

• ADH increases the permeability of the collectingtubules and distal tubules to water so more isreabsorbed

• This decreases the total volume of urine

• Alcohol inhibits the release of ADH, so lesswater is reabsorbed producing copious amountsof dilute urine (can cause dehydration)

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Vessels• Afferent and efferent arterioles associated with glomerular capillaries

– Allows high pressure for forcing filtrate out of blood

– About 20% of renal plasma flow is filtered each minute (125 ml/min): this is the glomerular filtration rate (GFR), an important clinical measure of renal function

• This is about one liter every 8 minutes (only 1% ends up as urine)

• Peritubular capillaries arise from efferent arterioles– Absorb solutes and water from tubule cells

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Histology

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For studying

Parts of the kidney:

1. Renal pyramid

2. Efferent vessel

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 vessel

13. Nephron

14. Minor calyx

15. Major calyx

16. Renal papilla

17. Renal column

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The UretersSlender tubes about 25 cm (10 “) long leaving each renal pelvis

One for each kidney carrying urine to the bladder

Descend retroperitonealy

خلف صفاقی

Enter posterolateralcorners of bladder

Run medially within posterior bladder wall before opening into interior

This oblique entry helps prevent backflow of urine

پس از لگنچه، روی عروق ایلیاک، : محل های تنگی حالب

انتهای حالب و ورود به مثانه

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Ureters play an active

role in transporting urine

(it’s not just by gravity)

layers of UretersTransitional epithelium of mucosa (مخاطی)

Muscularis (ماهیچه ای)– Inner longitudinal,

outer circular layers

– Inferior 3rd with extra longitudinal layer)

– Stimulated to contract when urine in ureter: peristaltic waves to propel urine to bladder

Adventitia (همبند)

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Urinary Bladder Collapsible muscular sac

Stores and expels urine: 250-300 cm3

Lies on pelvic floor posterior to pubic symphysis

Males: anterior to rectum

Females: just anterior to the vagina and uterus

See also brief atlas

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If full: bladder is spherical and extends into abdominal cavity (holds about 500 ml or 1 pt)

If empty: bladder lies entirely within pelvis with shape like upside-down pyramid

Urine exits via the urethra

Trigone is inside area between ureters and urethra: prone to infection (see slide 38)

Bladder wall layersMucosa with distensible transitional epithelium (can

stretch) مخاط قابل جمع شدن

Submucosa زیر مخاط

Thick muscularis called the detrusor muscleماهیچه صاف3 layers of highly intermingled smooth muscle

Fibrous adventitia سروز در سطح فوقانی

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UrethraSmooth muscle with inner mucosa

Drains urine out of the bladder and body

Male: about 20 cm (8”) long پروستاتیک، پرده ای، اسفنجی

Female: 3-4 cm (1.5”) long

Urethra____

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Urethral sphinctersInternal: involuntary sphincter of smooth muscle

External: skeletal muscle inhibits urination voluntarilyuntil proper time (levator anni muscle also helpsvoluntary constriction)

Males: urethra has

three regions (see

right)

1. Prostatic urethra__________

2. Membranous urethra____

3. Spongy or penile urethra_____

_________trigone

female

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Micturition (Voiding )

– Urinating

– Emptying the bladder

KNOW:

Micturition center of brain: pons

(but heavily influenced by higher centers)

Parasympathetic: to void

Sympathetic: inhibits micturition

Male Reproductive system

دستگاه تولید مثل مردانه

بیضه

اپیدیدم

مجرای منی بر

کیسه ی بیضی

آلت تناسلی خارجی

کیسه منی

غده پروستات

غده کوپفر38

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Gonads– testes (testosterone) = sex

characteristics

• muscle development and maturity

– ovaries (estrogen) = sex

characteristics

• maturity and coordination

Testis

Spermatogenesis

Oval organ, 4-5 cm x 2.5 cm in diameter

Tunica vaginalis احشایی و جداری

Tunica albuginea پردي سفید

Seminiferous tubulesلولً مىی ساز

Leydig cells ٌورمون : بیىابیىی

Sertoli cells (supportive)

Rete testis

Efferent ductules (لولً وابران) 40

Histology of the Testis

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Heat Exchange of Pampiniform Plexus

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Spermatic Ducts

Efferent ductules

12 small ciliated ducts collecting sperm from the rete testes

and transporting it to the epididymis

Epididymis (head, body & tail)

6 m long coiled duct adhering to the posterior of testis

site of sperm maturation & storage (fertile for 40 to 60 days)

Ductus (vas) deferens مجرای منی بر

muscular tube 45 cm long passing up from scrotum through

inguinal canal to posterior surface of bladder

Ejaculatory duct مجرای انزالی

2 cm duct formed from ductus deferens & seminal vesicle &

passing through prostate to empty into urethra

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Male Duct System

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Accessory Glands

Seminal vesicles کیسً ی مىی

posterior to bladder

empty into ejaculatory duct

Prostate gland

below bladder, surrounds urethra and ejaculatory duct

empty through pores in urethral wall

Bulbourethral (Cowper) glands

near bulb of penis

empty into penile urethra

lubricating fluid45

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Anatomy of the Penis

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Spermatozoon

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Semen (Seminal Fluid)

2-5 ml of fluid expelled during orgasm60% seminal vesicle fluid, 30% prostatic & 10% sperm and trace of bulbourethral fluid

normal sperm count is 50-120 million/ml (< 25 million/ml is associated with infertility)

sperm serve to digest path through cervical mucus and to fertilize egg

Other components of semen

fructose provide energy for sperm motility

fibrinogen

clotting enzymes convert fibrinogen to fibrin causing semen to clot

fibrinolysin liquefies semen within 30 minutes

prostaglandins stimulate female peristaltic contractions

spermine is a base stabilizing sperm pH at 7.2 to 7.6

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Female External Genitalia

Vulva: everything that is externally visible (mons pubis,

labia majora, labia minora, clitoris, urethral orifice,

vaginal vestibule, perineal body)

mons pubis: mound of fatty tissue above the pubic bone

labia majora: large, outer fatty folds of skin tissue

labia minora: inner folds of skin and erectile tissue

clitoris: small, highly sensitive organ

glans: tip of the clitoris

prepuce (clitoral hood): loose-fitting fold of skin covering

the clitoral glans

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Female External Genitalia

vaginal vestibule: the cleft containing the vaginal and urethral openings

Skene’s glands: group of small mucous glands that open into vaginal

vestibule (near urethra)

Bartholin’s glands: two glands that open into vaginal vestibule (on either

side of the vaginal opening) - thought to provide some lubrication, may

emit a pheromone

hymen: thin mucous membrane partially covering the vaginal opening

perineum: tissue between the genital and anus.

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External Female Genitalia

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Female Internal Genitalia

Vagina: tubular organ connecting external genitals with uterus

Grafenberg spot (g-spot):

mass of erectile and glandular tissue surrounding the urethra just below the

bladder

some women report that simulation to g-spot produces sexual arousal and

orgasm

uterus: hollow muscular organ - purpose to nurture developing

fetus

cervix: small lower portion of the uterus that projects into the vagina

Perimetrium: پوشش صفاقی

myometrium: layers of smooth muscle comprising the uterus

endometrium: inner lining of the uterus that builds a rich blood supply

and sloughs off the lining each month

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Female Internal Genitalia

ovaries: female gonads - containing the immature

female reproductive cells

ovum: female reproduce cell

fallopian tubes: thin flexible muscular structures

connecting the ovaries with the uterus - passageway

for the ovum to travel to the uterus

cilia: tiny hairlike projections that line the fallopian tubes

and propel the ovum towards the uterus

fimbriae: fringelike projections that reach out to the ovary

to draw a released ovum into the fallopian tube.

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Uterine tube

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Ovaries

The female gonads or sex glands

They develop and expel an ovum each month

A woman is born with approximately 400,000

immature eggs called follicles

During a lifetime a woman release 400 to 500

fully matured eggs for fertilization

The follicles in the ovaries produce the female

sex hormones, progesterone and estrogen

These hormones prepare the uterus for

implantation of the fertilized egg