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