The document provides detailed information on the anatomy and structures of the renal (kidney) system. It discusses the location and descriptions of the kidneys, ureters, urinary bladder, and urethra. It describes the internal structures of the kidneys including the cortex, medulla, renal pyramids, and nephrons. It discusses the microstructure of the nephrons and how they filter blood to form urine. It also discusses the blood supply, lymphatic drainage, and innervation of the kidneys.

1. A.SWAROOPA
MSC(NURSING)

2. VITAL ORGANS

3. Organs of the Renal System
• 2Kidneys
• 2Ureters
• Urinary bladder
• Urethra
• Not many
structures, but
very important!
Figure 23.1a3

4. Kidneys
LOCATION:
 Kidneys are a pair of excretory organs situated on the
posterior abdominal wall,
 above the waist,
 extending from upper border of T12 to L3 vertebra,
 partially protected 11th & 12th pairs of ribs.

5. Renal Anatomy
• Paired retroperitoneal bean-shaped organs
• Located in the dorsal upper lumbar region
• Encased in the renal fat pad

6. Kidneys
Right kidney is slightly lower than the left because the
liver occupies considerable space on the right side
superior to the kidney.
“THEY ARE THE RETRO PERITONEAL ORGANS”

7. KidneysCOLOR AND SHAPE:
Red color and bean shaped.
CAPSULES OR COVERINGS OF KIDNEYS
 Fibrous capsule,
 Peri-renal fat,
 Renal fascia and
 Para-renal fat

8. 11 cm
6cm
3cm
8
HEIGHT & WEIGHT:
Each kidney is 11 cm (4-5”) long, 6 cm (2-3”) broad and
3 cm (1”) thick, weight 150 g in males and 135 g in
females.

9. ORGANS ASSOCIATED WITH THE KIDNEYS
SUPERIORLY- RIGHT ADRENAL GLAND.
ANTERIORLY- RIGHT LOBE OF THE LIVER ,
DUODENUM, & HEPATIC FLEXTURE OF THE COLON.
POSTERIORLY-12TH RIB DIAPHRAGM, MUSCLES OF
POSTERIOR ABDOMINAL WALL (PSOAS MAJOR,
QUADRATUS LUMBORUM & TRANSVERSUS
ABDOMINIS.

11. Peritoneal relations:
The kidneys are
retroperitoneal.
Certain areas of each
kidney are covered in
anteriorly by peritoneum,
whereas others are "bare“.

12. 12

13. Internal Structure of the Kidney
Renal pyramids
Renal papilla
Renal Columns
Renal Lobe
13

14. Human Kidney

15. Protection of the Kidneys
• 3 layers of connective
tissue:
– Inner layer- Renal capsule
– Middle layer- Adipose
capsule
– Outer layer-Renal fascia
Renal cortex
Retroperitoneal space
15

16. 3 layers of tissue surrounds the each
kidney
DEEP LAYER ( RENAL CAPSULE ) is a smooth
transparent sheet of dense irregular connective tissue
that continous with the outer coat of the ureter. It
serves as barrier against trauma and helps to
maintain the shape of kidney.

17. Middle layer: the adipose capsule : is a mass
of fatty tissue surrounding the renal capsule.
it also protects the kidney from trauma.
Superficial layer: renal fascia is another thin
layer of dense irregular connective tissue that
covers surrounding structures and to the
abdominal wall.

18. GROSS STRUCTURE OF THE KIDNEY
Longitudinal section there are 3 areas.
I. Fibrous capsule
II. Cortex
III. Medulla

19. 19
RENAL FIBROUS CAPSULE: surrounds the kidney,
made of dense fibrous connective tissue.

20. 20
CORTEX: A reddish brown layer of tissue
immediately below the capsule and out side the
pyramids.

21. 21
MEDULLA: the inner most layer consisting of pale
conical shaped striations called renal pyramids.

22. Surface anatomy of the Kidney
• Hilum is located on
the medial surface
HILUM: it is the concave medial border or deep
fissure of the kidney where the renal blood & lymph
vessels , urater & nerve enters.
Renal Sinus:
Space within hilus.
Kidneys receive
blood vessels and
nerves.

23. 23
RENAL PELVIS: it is the funnel shaped structure
which acts as a receptacle of the urine formed by
the kidney.

24. IT HAS NUMBER OF DISTAL BRANCHES CALLED CALYCES ,
EACH OF WHICH SOROUNDS APEX OF THE RENAL PYRAMID.
URINE FORMED IN THE KIDNEY PASES THROUGH PAPILLA
AT THE APEX OF THE PYRAMID INTO MINOR CALYX THEN
INTO MAJOR CALYX BEFORE PASSING THROUGH THE PELVIS
INTO THE URETER.

25. 25
THE WALLS OF THE PELVIS CONTAINS SMOOTH
MUSCLE AND ARE LINED WITH TRANSITIONAL
EPITHELIUM.
PERISTALYSIS OF THE SMOOTH MUSCLE IN THE
WALLS OF THE CALYCES PROPELS URINE
THROUGH THE PELVIS , URETERS TO THE
BLADDER.

26. The ureteric pelvis usually divides into two or
three short tubes, the major calices, each of
which subdivides into 7 to 14 minor calices.
Each minor calyx receives the openings of
collecting tubules on papillae that project into
the calices

27. Intravenous pyelogram:
Note the calices and the
pelves of the ureters,
which differ in shape and
level.

28. Renal Pedicle:
The ureter and renal
vessels near the hilus form
the pedicle.
The renal vein anterior, the
ureter is posterior, and the
arteries little high.

29. The glomerular capillaries called the glomerulus.
The usual direction of blood flow is:
• Arteries
• Arterioles
• Capillaries
• Venueles
• veins

30. BLOOD SUPPLY TO KIDNEY
ARTERIAL SUPPLY
ABDOMINAL AORTA
RENAL ARTERIES
SEGMENTAL ARTERIES
INTERLOBAR ARTERIES
ARCUATE ARTERIES
INTER LOBULAR
FORMS 5-8 CAPILLARIES

32. BLOOD SUPPLY TO KIDNEY
VENOUS SUPPLY
INFERIOR VENACAVA
RENAL VEINS
SEGMENTAL VEINS
INTERLOBAR VEINS
ARCUATE VEIN
INTER LOBULAR VEINS

34. The Blood Supply to the Kidneys

35. Regulates blood flow to the kidney by
causing vasodilation or vaso constriction of
renal arterioles.
Autonomic plexuses in the abdomen and pelvis

37. Filtering & phagocytosis
Proliferation of
lymphocytes

38. Lumbar aortic
nodes

39. MUSCLES ATTACHEDTO KIDNEYS
QUADRATUS
LUMBORUM
MUSCLE
ILLIACUS MUSCLE
PSOAS MAJOR
MUSCLE

40. 40
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

41. MICROSCOPIC ANATOMY OF THE KIDNEYS
• The functional unit of the lungs is the
alveolus.
• The functional unit of the liver is the lobule.
• The functional unit of the kidney is the
NEPHRON and smaller number of collecting
tubules.
• Each kidney has about 18 lobes and 1 million
nephrons.
41

44.  Cortical nephrons with short loop of Henle.
 Juxtamedullary nephrons with long loops of Henle.
Two types of nephrons

45. CORTICAL NEPHRONS
i. 85% of nephrons
are in this type.
ii. Most of the parts of
nephron are in
cortex only.
iii. Length of LH is
short.
iv. Accompanied by
peritubular
capillary net work.
JUXTRA MEDULLARY
NEPHRONS
i. 15%.
ii. begins at the junction
of the cortex and
medulla.
iii. long.
iv. vasa recta.
DIFFERENCES BETWEEN TYPES OF NEPHRON

51. The glomerular filtration membranes are consist of 3
layers of capillary wall.
---Endothelium.
---Basement membrane.
---Epithelial podocytes.
Fluid that filtered from the capillary blood into the
bowman's space is called filtrate and forms the
primary urine .

52. Histology of Filtration Membrane
1) Endothelium of glomerulus
– Single layer of capillary endothelium with
fenestrations
– Prevents RBC passage; WBCs.

53. Histology of Filtration Membrane
2) Basement membrane of glomerulus
– Between endothelium and visceral layer of glom. capsule
– Prevents passage of large protein molecules

54. Histology of Filtration Membrane
3) Filtration slits in podocytes
– Podocytes
• specialized epithelium of visceral layer
• footlike extensions with filtration slits between extensions
– Restricts passage of medium-sized proteins

55. THE FILTRATE THEN DIFFUSES ACROSS BOWMANS SPACE
AND INTO THE TUBULES OF THE NEPHRON.
IN THE TUBULES SOME SUBSTANCES ARE ADDED TO THE
FILTRATE AS PART OF THE URINE FORMATION.
AND SOME SUBSTANCES REABSORBED OUT OF THE FILTRATE
AND BACK IN TO THE BLOOD.

57. LOOP OF HENLE
REABSORPS THE WATER AND IONS FROM THE URINE
• AND CONTROLS THE CONCENTRATION OF URINE.
–THICK PORTION
–THIN PORTION
• DISTAL CONVOLUTED TUBULE: regulate Na, K, PH
AND FURTHER DILUTION OF URINE TAKES PLACE.
• COLLECTING DUCT WHICH JOINS WITH SEVERAL
TUBULES TO COLLECT THE FILTRATE AND FINAL NA
REGULATION TAKES PLACE.
57

58. PROXIMAL CONVOLUTED TUBULE (PCT)

59. LOOP OF HENLE

60. Descending limb of the loop of henle

61. ASCENDING LIMB OF THE LOOP OF HENLE

62. DISTAL CONVOLUTED TUBULE( DCT)

63. COLLECTING DUCT

64. TUBULE HISTOLOGY
• PCT : cuboidal cells with apical microvilli
• Descending Loop and beginning of Ascending
Loop: simple squamous epithelium.
• Ascending limb of the Loop:
–cuboidal & columnar epithelial cells.
• DCT, collecting ducts :
–cuboidal with specialized cells.

65. The Nephron

66. JUXTAGLOMERULAR APPARATUS
 The distal end of the renal
tubule passes next to the
glomerulus to form the
juxtaglomerular
apparatus (juxta means
“next to”).
 The juxtaglomerular
apparatus (JGA) consists
of cells located in and
around the glomerulus
and the glomerular
capsule.
66

68. KIDNEY FUNCTIONS

69. The ureter is continous with the funnel
shaped renal pelvis.
The ureters are the tubes that convey urine
from the kidneys to the urinary bladder.
URETERS
The two ureters are muscular tubes that
extend from the kidneys to the posterior
surface of the urinary bladder where the
urine is propelled along the ureter by
peristaltic contractions

70. The ureter is a retroperitoneal, distensible muscular
tube that connects the kidney with the bladder.

71. Because of this arrangements (psoas major
muscle, sacro illiac joint , posterior wall of the
bladder ) when urine accumulates and the
pressure in the bladder rises, the ureters are
compressed and the openings occluded. This
prevent reflux of urine into the ureters (towards
kidneys).

72. Ureter relations
• It lies within the hilum of the
kidney and receives the major
calyces
• It enters the pelvis by crossing
the bifurcation of the common
iliac artery in front of the
sacroiliac joint
• It runs downward & forward
on the lateral wall of the pelvis
to enter the lateral angle of
the bladder

73. RELATIONS TO URETERANTERIOR:
• Duodenum,
• Terminal part of the ileum,
• Right colic vessels,
• Iliocolic vessels,
• Right testicular or ovarian vessels.
POSTERIOR:
• Right psoas muscle,
• Bifurcation of the
right common iliac artery

74. CONSIST OF 3 LAYERS OF TISSUE:
1) Outer covering of fibrous tissue.
2) Middle muscular layer consisting of smooth muscle fibers.
3) Inner layer
the mucosa,
lined with transitional
epithelium.

76. Blood Supply• Upper end is supplied by
the renal artery
• Middle portion by
(gonadal) testicular or
ovarian artery
• In the pelvis is supplied
by the superior vesical
artery

77. The lymph drains to the lateral aortic nodes
and the iliac nodes

78. Sympathetic supply
from renal,
Testicular, ovarian
hyogastric & pelvic
plexus.
Para sympathetic
supply from sacral
plexus.

79. Ureters
• Each ureter has three
constrictions along its
course,
• 1- Where the renal pelvis
joins the ureter,
• 2- As it crosses the pelvic
brim,
• 3- Where it pierces the
bladder wall ( intra-mural
part)

81. SUPRARENAL GLANDS
• The two suprarenal glands
are yellowish
retroperitoneal organs that
lie on the upper poles of the
kidneys
• They are surrounded by the
renal fascia
• Separated from the kidneys
by the perirenal fat
• Each gland has a yellow
cortex and a dark brown
medulla

82. LEFT SUPRARENAL
GLANDS
• Left suprarenal gland is
crescentic in shape.
• Extends along the medial
border of the left kidney from
the upper pole to the hilum
• It lies behind the:
• The pancreas,
• The stomach
• It rests posteriorly on the
diaphragm

83. RIGHT SUPRARENAL
GLANDS• The right suprarenal gland
is pyramidal in shape and
caps the upper pole of the
right kidney.
• It lies behind the right lobe
of the liver and extends
medially behind the IVC.
• It rests posteriorly on the
diaphragm.

85. Suprarenal Glands• The cortex secretes hormones
include:
• Mineral corticoids, which
control fluid and electrolyte
balance.
• Glucocorticoids, which control
carbohydrates, fats, and
proteins.
• Sex hormones, which probably
play a role in the prepubertal
development of the sex organs
• The medulla secretes the
catecholamine, epinephrine
and norepinephrine

86. Blood SupplyARTERIES:
Three arteries supplying each gland,
• 1- Superior suprarenal artery: from
inferior phrenic artery
• 2- Middle suprarenal from aorta.
• 3- Inferior suprarenal from renal.
VEINS:
• A single vein emerges from the hilum
of each gland:
• The right suprarenal vein drains into
the IVC .
• The left suprarenal vein drains into the
left renal

88. 88
URINARY BLADDER • Collapsible muscular sac.
• Stores and expels urine.
• Lies on pelvic floor
posterior to pubic
symphysis.
– Males: anterior to
rectum.
– Females: just anterior to
the vagina and uterus.

89. The Final Common Pathway
• Urinary bladder
– hollow muscular organ
– generally smaller in females due to presence of a
uterus
– retroperitoneal in the pelvic cavity, posterior to the
pelvic symphysis
– freely movable.
– Bladder muscle is detrusor muscle.

90. 90

91. 91

92. The openings of the two ureters and the urethra mark a
triangular area called the trigone on the bladder floor.
S
T
R
U
C
T
U
R
E
OF
“TRIGONE”

93. Bladder- structure
3 layers
– Outer layer
• Loose connective tissue
– Middle layer
• Smooth muscle and
elastic fibres
– Inner layer
• Lined with transitional
epithelium
93

94. • Bladder histology:
– Sphincters control entry from ureters.
– Exit at the urethra.
• circular smooth muscle fibers form internal urethral
sphincter.
• lower is the external urethral sphincter with skeletal
muscle for voluntary control.

95. URETHRA
–small tube from floor of bladder to exterior
of body.
• females -- fairly straight path exits anterior to
vagina.
• males -- passes through the prostate gland
and exits through the penis.

96. The Urethra
- conveys urine from the urinary bladder to the
outside of the body.
FEMALES MALE
3-4 cm (1.5”) 20 cm (8”)
greater risk of
urinary tract
infections

97. The male urethra has three regions:
1) prostatic urethra
2) membranous urethra
3) penile urethra.
Difficulty in voiding urine with
enlarged prostate

98. URETHRAL SPHINCTERS IN BOTH SEXES:
-Internal Urethral Sphincter- under involuntary control of
smooth muscle.
-External Urethral Sphincter - under voluntary control of skeletal
and levator ani muscle.
internal urethral sphincter
external urethral sphincter

99. HISTOLOGY
FEMALE: THREE COATS
Inner mucosa,
Intermediate thin layer of spongy tissue with plexus of
veins.
Outer muscular coat continuous with the bladder.
MALE TWO LAYERS
Inner mucous membrane and a muscularis
Outer submucosa tissue with various accessory structures
which connect to it.
Both genders have a stratified squamous epithelial
lining.

100. 100
KNOW:
-Micturation center of
brain: pons.
-Parasympathetic: to
void.
-Sympathetic: inhibits
micturation.

102. CONGENITAL ANOMALIES OF KIDNEY:
AGENESIS (one or both fetal kidney are absent).
HYPOPLASIA (Small kidney).
ECTOPIC KIDNEYS (kidney is located in an abnormal position.
HORSE SHOE KINEYS (the kidneys are fused together at the lower
end or base.)
PAN CAKE KIDNEYS (renal fusion anomaly of the kidneys of the
crossed fused variety)
POLY CYSTIC KIDNEY (progressive enlargement of cysts in the
kidneys )

103. HYPOPLASIA ECTOPIC KIDNEY
HORSE SHOE PCKD PANCAKE KIDNEY

104. Epispadias & hypospadias:
Mutual opening located on dorsal or superior surface of the
penis. Ventral or inferior surface of the penis.

107. Addison’s disease, chronic adrenal insufficiency,
hypocortisolism, and hypoadrenalism) is a rare,
chronic endocrine systemdisorder in which the adrenal
glands do not produce sufficient steroid
hormones (glucocorticoids and often mineralocorticoids)

110. Urinary tract
infections
is the inability to
empty the
bladder completely.
URINARY
RETENTION

111. CHRONIC
RENAL
FAILURE

112. Dialysis
the clinical purification of blood by dialysis, as a
substitute for the normal function of the kidney.