histology of upper urinary tract

1. Histology practical
(Histology of Urinary System)
By : Osama Al-Zahrani
@OSAMA_Z96

2. Kidney
* Component & Characteristics :
1- Cortex.
2- Medulla.
3- Major calyx (Transitional epithelium).
4- Minor calyx.
5- Renal Pelvis (Transitional epithelium).
6- Collecting duct.
7- Glomeruli.
8- Proximal Convoluted Tubule (PCT).
9- Distal Convoluted Tubule (DCT).
* Function :
1- Blood filtration.
2- Hormones production.
3- Minerals absorption.
* Histopathological findings :
- Amyloid degeneration of the kidney.
Minor calyx
Cortex
Glomeruli
Major calyx
Renal Pelvis
Cortex
Medulla
Collecting ducts

4. Adventitia
Ureter
* Component & Characteristics :
1- Transitional Epithelium (Stratified cuboidal).
2- Musculosa :
A) Upper 2/3 :
- Inner longitudinal.
- Outer circular.
B) Lower 1/3 :
- Inner longitudinal.
- Middle circular.
- Outer longitudinal.
3- Adventitia.
4- Narrow (Star-shaped) lumen.
* Function :
- Conduct the urine from the kidney to the urinary bladder.
* Histopathological findings :
1- Ureteritis Glandularis.
2- Ureteritis Cystica.
Narrow
(Star-shaped)
Lumen
Transitional Epithelium

6. Urinary Bladder
* Component & Characteristics :
1- Transitional epithelium (Urothelium).
2- Umbrella cells :
Bulbous, dome-shaped, 1-2 nuclei with vesicular plaques.
3- Mucosa :
(Transitional epithelium & Lamina propria), Highly folded when empty.
4- Musculosa :
All directions : circular, longitudinal, oblique.
5- Wide lumen.
* Function :
Urine storage.
* Histopathological findings :
1- Cystitis Glandularis.
2- Cystitis Cystica.
Transitional epithelium
with umbrella cells
Wide Lumen
Mucosa

8. Juxtaglomerular Apparatus
* Component & Characteristics :
1- Juxtaglomerular cells.
2- Macula densa cells.
3- Mesangeal cells (Extraglomerular).
4- Parietal layer of Bowman`s capsule.
5- Visceral layer of Bowman`s capsule.
6- Efferent arteriole.
7- Afferent arteriole.
8- Proximal Convoluted Tubule (PCT).
9- Distal Convoluted Tubule (DCT).
* Function :
Regulate blood pressure and the filtration rate of
the glomerulus.
* Histopathological findings :
1- Membranous Glomerulonephritis
2- Focal segmental Glomerulonephritis
3- Crescentic Glomerulonephritis
4- Chronic Glomerulonephritis
Visceral layer of
Bowman`s capsule
Parietal layer of
Bowman`s capsule
Mesangeal cells
Macula densa
DCT
PCT

10. Proximal & Distal Convoluted Tubule
* Component & Characteristics :
1- Proximal Convoluted Tubule (PCT) :
A) High cuboidal cells.
B) Apical many microvilli.
C) Full parallel mitochondria in basal Striations.
D) Narrow lumen.
2- Distal Convoluted Tubule (DCT).
A) Low cuboidal cells.
B) Few microvilli.
C) Few basal Striations.
D) Wide lumen.
3- Glomerulus.
4- Parietal layer of Bowman`s capsule.
5- Visceral layer of Bowman`s capsule.
* Function :
- Secretion and Reabsorption.
* Histopathological findings :
1- Acute tubular necrosis.
Proximal Convoluted Tubule
(PCT)
Distal Convoluted Tubule
(PCT)
Visceral layer of Bowman`s capsule Parietal layer of Bowman`s capsule