In the name of God
Anatomy:
Genitourinary System
Moradian MD, MPH, PhD Candidate
Tehran University of Medical Sciences
[email protected]
2013
Pearson, Inc.,
Pearson Benjamin
Cummings 2009
Dr. Budgie
Hussain
‫عملکردهای اصلی دستگاه ادراری‬
‫کلیٍ‏َا‏خًن‏را‏فیلتر‏می‏کىىذ‏تا‏مًاد‏زیر‏را‏از‏آن‏تسدایىذ‪:‬‬
‫سمًم ‏‪ ،‬‏محصًالت ‏ديرریختىی ‏سًخت ‏ي ‏ساز‪ ،‬‏آب ‏زیادی‏‬
‫تذن‏ي‏یًوُای‏زیادی‏تذن‬
‫مًارد ‏دير ‏ریختىی ‏حايی ‏ویتريشن ‏مثل‪ :‬‏ايرٌ‪ ،‬‏اسیذ ‏ايریک ‏ي‏‬
‫کراتیىیه‬
‫تعادل‏آب‪،‬‏الکتريلیت‏َای‏تذن‏ي‏سطح‏اسیذ‪-‬تاز‏تذن‏را‏حفظ‏‬
‫میکىذ‏(رویه)‬
‫‏‬
‫اریتريپًئتیه‏را‏کٍ‏محرک‏خًن‏سازی‏در‏مغس‏استخًان‏است‏‬
‫را‏ترشح‏می‏کىىذ‪.‬‬
‫‪2‬‬
Main Functions of Urinary System
Kidneys 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
3
The Urinary System
Paired kidneys‫کلیٍ‏َا‏‏‏‬
A Ureter for each kidney
‫حالة‬-‫میسوای‬
Urinary bladder
‫مثاوٍ‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‏‬
Urethra
ٌ‫پیشاترا‬
4
‫خلف صفاق‬
Kidneys are retroperitoneal organs
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
*
*
5
6
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
8
Note layers of adipose
(fat), capsule, fascia
Transverse sections show
retroperitoneal position of
kidneys
Note also: liver, aorta
muscles on CT
9
Kidney regions
Cortex: outer
Columns of cortex divide medulla into “pyramids”
Medulla: inner
Darker, cone-shaped medullary or renal pyramids
Parallel bundles of urine-collecting tubules
10
Kidney Structure
The human kidney has lobes
Pyramid and cortical tissue surrounding it
5-11 per kidney
Renal pelvis (=basin)
Expanded, funnel shaped, superior part of
ureters
Branches to form two or three major calices
Each of these divides again, minor calices:
collect urine from papillae of pyramids
11
12
Kidney Structure
Nephron
‫ وفرون‬:ً‫واحد ساختماوی کلی‬
ً‫جسمک کلی‬
Renal corpuscle (in cortex)
Glomerulus (tuft of capillaries)
Glomerular (Bowman’s) capsule
‫گلومرول‬
‫کپسول بومه‬
Tubular section
Proximal convoluted tubule
Loop of Henle
Distal convoluted tubule
Collecting duct
‫لولً پیچیدي وسدیک‬
ً‫قوش ٌىل‬
‫لولً پیچیدي دور‬
‫مجرای جمع کىىدي‬
13
Nephron
14
The Kidney and the 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
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
16
Scanning EM of podocytes clinging to
capillaries (left) and filtration membrane
The capillary pores (fenestrations)
diagram (right)
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
17
Classes of
nephrons
• Cortical nephrons
– 85% of all
nephrons
– Almost entirely
within cortex
• Juxtamedullary
nephrons
– Renal corpuscles
near cortexmedulla junction
22
The collecting ducts
• The most important role is to conserve body
fluids
• When the body must conserve water, the
posterior pituitary gland secretes ADH
(antidiuretic hormone)
• ADH increases the permeability of the collecting
tubules and distal tubules to water so more is
reabsorbed
• This decreases the total volume of urine
• Alcohol inhibits the release of ADH, so less
water is reabsorbed producing copious amounts
of dilute urine (can cause dehydration)
24
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
25
Histology
26
27
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
28
The Ureters
Slender tubes about 25
cm (10 “) long leaving
each renal pelvis
One for each kidney
carrying urine to the
bladder
Descend retroperitonealy
‫خلف صفاقی‬
Enter posterolateral
corners of bladder
Run medially within
posterior bladder wall
before opening into
interior
This oblique entry helps
prevent backflow of
29
urine
‫محل های تنگی حالب‪ :‬پس از لگنچه‪ ،‬روی عروق ایلیاک‪،‬‬
‫انتهای حالب و ورود به مثانه‬
layers of Ureters
Transitional epithelium
of mucosa (‫)مخاطی‬
Muscularis (‫)ماهیچه ای‬
Ureters play an active
role in transporting urine
(it’s not just by gravity)
– 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
31
Urinary Bladder
See also brief atlas
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
32
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)
33
Bladder wall layers
Mucosa with distensible transitional epithelium (can
stretch) ‫مخاط قابل جمع شدن‬
Submucosa ‫زیر مخاط‬
Thick muscularis called the detrusor muscle‫ماهیچه صاف‬
3 layers of highly intermingled smooth muscle
Fibrous adventitia ‫سروز در سطح فوقانی‬
Urethra
Smooth muscle with inner mucosa
Drains urine out of the bladder and body
Male: about 20 cm (8”) long
Female: 3-4 cm (1.5”) long
‫ اسفنجی‬،‫ پرده ای‬،‫پروستاتیک‬
Urethra____
35
Urethral sphincters
Internal: involuntary sphincter of smooth muscle
External: skeletal muscle inhibits urination voluntarily
until proper time (levator anni muscle also helps
voluntary constriction)
Males: urethra has
three regions (see
right)
_________trigone
1. Prostatic urethra__________
2. Membranous urethra____
3. Spongy or penile urethra_____
female
36
Micturition (Voiding )
– Urinating
– Emptying the bladder
KNOW:
Micturition center of brain: pons
(but heavily influenced by higher
centers)
Parasympathetic: to void
Sympathetic: inhibits micturition
37
‫‪Male Reproductive system‬‬
‫دستگاه تولید مثل مردانه‬
‫بیضه‬
‫اپیدیدم‬
‫مجرای منی بر‬
‫کیسه ی بیضی‬
‫آلت تناسلی خارجی‬
‫کیسه منی‬
‫غده پروستات‬
‫غده کوپفر‬
‫‪38‬‬
Gonads
– testes (testosterone) = sex
characteristics
• muscle development and maturity
– ovaries (estrogen) = sex
characteristics
• maturity and coordination
39
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
41
Heat Exchange of Pampiniform Plexus
42
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
43
Male Duct System
44
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 fluid
45
46
Anatomy of the Penis
47
Spermatozoon
48
Semen (Seminal Fluid)
2-5 ml of fluid expelled during orgasm
60% 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
49
50
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
51
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.
52
External Female Genitalia
53
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
54
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.
55
56
Uterine tube
57
58
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
59