URINARY SYSTEM
• Ren (kidney)
• Excretory passages
- calyx renalis
- pelvis renalis
- ureter
- vesica urinalis
- urethra
Kidney (ren, nephros)
Cortex:
- cortex corticis
- pars radiata corticis
- columnae renales
(Bertini)
Medulla:
- pyramides renales (10 – 18)
- papillae renales
- foramina papillaria na area
cribrosa
Capsula fibrosa
Capsula adiposa
Renal corpuscules
Blood supply:
a. renalis
aa. segmentales
aa. interlobares
aa. arcuatae
aa. corticales radiatae
aa. interlobulares
afferent arteriole
• glomerulus
efferent arteriole
• peritubular capilary network
+ vasa recta
vv. corticales radiatae
vv. interlobulares
vv. arcuatae
vv. interlobares
vv. renales
(* portal circuit)
Cortical nephron
Juxtamedullar
nephron
Medullary ray
A. corticis radiata
Peritubular
capilary network
V. corticis radiata
V. arcuata
Vasa recta
MEDULLA
CORTEX
• Functional secretory unit
nephron
• Excretory units
collecting ducts (tubulus et ductus colligens)
ductus papillares
Renal corpuscule
corpusculum renis
(Malpighi)
Glomerulus
Capsula glomeruli
(Bowman)
Renal (uriniferous) tubule
tubulus renis
Tubulus proximalis
Ansa nephroni (Henle)
Tubulus distalis
Nephron
Corpusculum renis ( 200 μm)
arteriola afferens + efferens
Glomerulus
Urinary (Bowman’s)
space
Uriniferous pole
Vascular pole
Bowman’s capsule:
parietal layer
visceral layer
+ mesangium
Corpusculum renis
Filtration barrier
• Glomerular endothelial cells – fenestrations (pores) w/o diaphragm
• Laminae basales of endothelium and podocytes:
1. lamina rara subendothelialis,
2. lamina densa
3. lamina rara subepithelialis
l. densa: collagen IV , l. rarae: heparansulphate
• podocytes – filtration slit membrane – similar to a diaphragm spanning
fenestrations in normal capillaries
Filtration barrier
0,02 – 0,04 μm
Ren (Weigert-vanGieson)
tubulus proximalis
tubulus distalis
Ren (HE) – corpusculum renis, uriniferous pole 
p
p
d
Ren (HE): corpusculum renis – vascular and uriniferous pole
Tubulus renis
Distal
tubule Proximal
tubule
Loop of henle
Simple columnar
epithelium + brush
border
Simple squamous
epithelium
(thin segment)
Simple cubic
epithelium
(thick segment)
Simple cubic
epithelium
Simple cubiccolumnar
epithelium
Ren – proximal tubule (ELM): brush border, basal labyrinth
Ren – proximal tubule (ELM): brush border, basal labyrinth
Ren (Weigert-van Gieson) - medulla
Ren (HE): medulla Loop of Henle – thin segment
Loop of Henle – thick segment
ductus colligens
Ren – medulla (HE)
Ren (HES) – medulla: thin segment of Loop of Henle (longit.)
Juxtaglomerular apparatus
(renin & erytropoetin)
Endocrine kidney cells:
• juxtaglomerular cells (modified leiomyocytes of the wall of vas afferens)
• macula densa (cells of distal tubule)
• mesangial cells (extraglomerular mesangium – modified fibroblasts
intercalated between capillaries in the vascular pole
(intraglomerular mesangium – pathologic relevance – inflammation – collagen
deposition)
Juxtaglomerular apparatus
area cribrosa
Papilla renalis
Area cribrosa on papilla renalis
foramina papillaria
medulla
transitional
[urotel]
Exctretory pasages
• intrarenal:
tubuli colligentes
ductus colligentes
ductus papillares
• extrarenal:
calyces minores
calyces majores
pelvis renalis
ureter
vesica urinalis
urethra (feminina, masculina)
Extrarenal excretory passages
• Mucosa - epithelium, lamina propria mucosae
• tunica muscularis - smooth muscle tissue arranged into two concetric
layers (or 3 – lower third of ureter, bladder)
• adventitia - (bladder – partially serosa)
(calyces et pelvis renalis, ureter, vesica urinalis, pars muralis urethrae)
Transitional epithelium
Empty
m. detrusor contracted
Full
m. detrusor relaxed
Uroplakin
Adaptation to volume
changes and osmotic
resistance
Cell architecture
Membrane flexibility
Rigid layer of uroplakin
doi: 10.1242/​jcs.00811
Calyx renalis (HE)
artery
Ureter:
- Mucosa (folds) – transitional epithelium + l. propria
- Submucosa
- Muscularis externa – long., circ., (lower third - long.)
- Adventitia
Ureter (HEŠ)
Ureter (HE)
Ureter (HE)
Vesica urinalis
Vesica urinalis
Vesica urinalis (HE)
Vesica urinalis (HE)
Urethra feminina
Mucosal folds
Stratified squamous epithelium
Lacunae urethrales
Paraurethral glands
Urethra feminina (HE)
Urethra masculina
• Pars intramuralis
– transitional ep.
• Pars prostatica
– transitional ep.
od colliculus seminalis:
– pseudostratified columnar.ep.
• Pars diaphragmatica
– stratified columnar ep.
– Tunica musc: m. sphincter urethrae
ext.
• Pars cavernosa
– stratified columnar ep.
fossa navicularis:
– Stratified squamous
– Lacunae urethrales Morgagni
Urethra masculina – pars spongiosa
Gll. paraurethrales (Littré)
lacunae urethrales
(Morgagni)
Pars cavernosa urethrae masculinae (HE)
stratified columnar. epithelium
4.
Urinary system
Slides:
30. Ren(HE)
31. Ren (Weigert-van Gieson)
32. Calyx renalis(HE)
33. Ureter(HE)
34. Vesica urinalis (HE)
35. Urethra feminina(HE)
41. Penis – urethra masculina (HE)
Atlas EM:
basal labyrinth (49)
filtration membrane (41)