Histology of kidney

2. HISTOLOGY OF
KIDNEY
Dr Iram Tassaduq

3. GENERAL ORGANIZATION
OF RENAL STRUCTURE
 Capsule
 Cortex
• Cortical labryinth
• Medullary rays
 Medulla
• renal pyramids
• cortical/renal columns
 Renal pelvis
 Major and minor
calyxes

6. LOBES AND LOBULES
 Each kidney lobe
consists of a medullary
pyramid and its
associated cortex.
 A renal lobule is
defined as a portion of
the kidney containing
those Nephrons that are
served by a common
collecting duct.

7. BLOOD SUPPLY

8. RENAL CAPSULE
 Comprised of 2
layers
 Outer mainly
consist of collagen
fibers
 Inner mainly has
myofibroblast

9. URINEFEROUS TUBULE
 Nephron
 Collecting
tubule

10. PARTS OF NEPHRON

11. RENAL CORPUSCLE

12. CORTICAL LABYRINTH
 Renal corpuscle
 Convoluted
tubule

13. BOWMANS CAPSULE

14. GLOMERULUS

19. MESENGIAL CELLS
 found within the
glomerulus. These
cells secrete a matrix
of basement
membrane-like
material to support
the structure of the
glomerulus.

20. PROXIMAL CONVULATED
TUBULE
 Longest and tortous part
of nephron
 Commences at urinary
pole
 Occupies major part of
cortex
 Lined by low columnar
epithelium
 Show brush border
 Absorb sodium

21. LOOP OF HENLE
 The thin segment of Henle's loop leads
into the straight part of the distal tubule,
which is formed by low cuboidal cells
without a brush border. A few short
microvilli are present
 Epithelial cells in the ascending parts of the
intermediate and straight distal tubules cells
transport chloride (active) and sodium ions
(passive) out of the tubular lumen into the
surrounding peritubular space.
 The epithelium can not be penetrated by
water. Consequently, the transport of ions
over the epithelium sets up a gradient in
osmotic pressure, which serves as driving
force in the further concentration of the
urine.

22. DISTAL CONVULATED
TUBULE
 Slightly tortous
 Lined by simple
cuboidal epithelium
 Absorption of sodium
and chloride

25. COLLECTING DUCT
 Excretory ducts
 Present in
medullary ray
 Lined by simple
cuboidal
epithelium
 Transport urine
from nephron to
renal pelvis

26. MEDULLARY RAYS
 Formed of straight
tubules and
collecting duct

27. JUXTA GLOMERULAR
COMPLEX

28. MACULA DENSA
 Specialized region of
DCT
 Cells are tall columnar
 Closely packed nuclei
 Thin and discontinuous
basal lamina
 Release renin

29. JUXTA GLOMERULAR
CELLS
 Present adjacent to
macula densa
 Epithelioid cells in
tunica media
 Large in size
 Internal elastic lamina is
absent

30. EXTRA GLOMERULAR
MESENGIAL CELLS
 Form a cushion of cells
between afferent and
efferent arteriole
 Structurally resemble
intraglomerular cells
 Functional significance
not clear