Kidney Histology Flashcards
dWhat are the two different types of kidney nephrons? [2]
Which is more common?
Cortical nephrons:
* 85%
* Shorter LoH
* Make less concentrated urine
Juxta-medullary nephrons:
* 15%
* Longer LoH
* Make more concentrated urine
At the centre of the renal corpuscle is the []
At the centre of the renal corpuscle is the glomerulus
Which of the following is the PCT?
A
B
C
D
E
Which of the following is the PCT?
A
B
C
D
E
Which of the following is the mesengial cell?
A
B
C
D
E
Which of the following is the PCT?
A
B
C
D
E
Which of the following is the podocyte?
A
B
C
D
E
Which of the following is the podocyte?
A
B
C
D
E
Which of the following is the bowmans space?
A
B
C
D
E
Which of the following is the bowmans space?
A
B
C
D
E
What is the role of mesengial cells in the glomerulus? [1]
Produce basement membrane of glomerulus
Which structures are located at the urinary pole of renal corpuscle? [1]
Which structures are located at the vascular pole of renal corpuscle? [1]
Urinary pole: where blood plasma starts journey into PCT
Vascular pole: where afferent arterioles become efferent arterioles
In the renal corpuscle, the plasma has to pass through a filtration barrier of three layers of what to enter Bowman’s space? [3]
The capillary endothelium, the podocyte layer, and their fused basement membrane
The endothelial cells in renal corpsucle are:
continuous
discontinuous
fenestrated
The endothelial cells in renal corpsucle are:
continuous
discontinuous
fenestrated
Which layer is the outermost layer of glomerulus
capillary endothelium
podocyte layer
fused basement membrane
Which layer is the outermost layer of glomerulus
capillary endothelium
podocyte layer
fused basement membrane
Label A-E of renal corpsucle
A: podocyte
B: Bowmans space
C: Foot process (of podocytes)
D: basement membrane
E: endothelial cell
Describe the structure of the podocyte foot processes [2]
Podocytes extend processes that surround the capillaries
These processes form secondary processes called foot processes
Describe the structure of the podocyte foot processes [2]
Podocytes extend processes that surround the capillaries
These processes form secondary processes called foot processes
Why should albumin not be able to pass through glomerular filtration barrier? [2]
podocytes create small space (less than 3.5 nm big)
albumin is negatively charged - is repelled by the negatively charged podocytes (particularly via podocyte protein called nephrin)
Explain what the role of podocyte slit diaphragm [1] and its components [2]
Part of podocyte foot processes that resists movement of molecules:
made from nephrin and podocins
Nephrin transmembrane protein that has a strong negative charge which repel protein from crossing into the Bowman’s space
Mutations to nephrin and podocins can lead to nephrotic syndrome
How are PCT cells specialised to have increased absorbtion? [1]
How can you tell PCT cells are PCT cells? [1]
Apical brush border
Large, deeply eosinophilic and some do not have nuclei visible
Label A-C
A: PCT
B: thin limb
C: thick ascending
How do you distinguish cells from LoH compared to PCT cells?
Question will say is from medulla of kidney
PCT: has brush border and smaller diameter
LoH: no brush border and much bigger diameter. cuboidal cell
How do you distinguish cells from the DCT? [3]
- smaller more lightly stained c.f. PCT
- more nuclei can be seen
- lack of brush border
- (less of them because DCT is smaller section of nephron)
Label A&B
A: PCT
B: DCT
Label A&B
A: DCT
B: PCT
Label A-C
A: PCT
B: mesengial cells
C: DCT
Which of the following are PCT and DCT?
Which cell types are found in the juxtaglomerular apparatus? [3]
What are their functions? [3]
The macula densa
* a collection of specialized epithelial cells of the distal convoluted tubule
* enlarged cells compared to surrounding tubular cells
* Sense sodium chloride concentration in the tubule, which in turn reflects the systemic blood pressure
The juxtaglomerular cells of the afferent arterioles
* Responsible for secreting renin
* Derived from smooth muscles cells of afferent arterioles
The extraglomerular mesangial cells
* Flat, elongated cells located near the macula densa
* Function is currently unclear
How can you distinguish that cells are from the CD?
- prominent lateral borders of the epithelial cells
- Cytoplasm of collecting duct cells is relatively clear (i.e., not as intensely eosinophilic as that of proximal or distal tubules)
- and cell borders are usually distinct.
Label A&B
A: DCT
B: PCT
Describe the different layers of the ureter [3]
- an inner longitudinal layer smooth muscle
- an outer circular layer of smooth muscle
- lumen of the ureter is covered by transitional epithelium
What are 3 parts of male urethra? [3]
Prostatic
Membranous
Penile (spongy)
Urethra:
Both male and female lined with [] which becomes [] at the terminal portion
Both male and female lined with transitional epithelium which becomes stratified squamous at the terminal portion
Describe pathophysiology of minimal change disease
Glomerulus appears norma under light microscopel but under electron microscope: loss of foot processes of the podocytes and glomerular filtration barrier
Loss of albumin: causes peripheral oedema, pitting oedema, puffy face and overall unwell
Describe pathophysiology of diabetic nephropathy
- Linked to high glucose
- Caused by thickening of basement membrane and matrix: causes stretching of podocytes and endothelial cells
- this creates Kimmelstiel–Wilson nodules
- creates micro-aneursyms: more likely to get blood plasma and albumin in the filtrate
- finally causes lipohyaline cap deposits and hyalinosis of afferent and efferent arterioles
Describe pathophysiology of Glomerulonephritis
- Membranous glomerulonephritis characterised by thickening of glomerular basement membrane due to presence of subepithelial immune deposits
- caused by autoimmune disease systemic lupus erythematosus (SLE) and production of self antigen antibodies beind deposited in the kidney:
- The deposition of the immune complex at the glomerular membrane is responsible for the inflammatory reaction at the glomerulus
Bladder cancer is almost always cancer of which cell type? [1]
What is most common symptom? [1]
Name one common cause [1]
Urothelial carcinoma (of the transitional cells)
Blood in urine
1/3 caused by smoking
Proximal convoluted tubule
Note the darker-stained cytoplasm and that fewer nuclei are visible. Also, microvilli in the lumen give the shaggy appearance on apical surface of the epithelial cells. Primary function is reabsorption of water, salts and small organic molecules (sugars, amino acids, etc.).
Contract logitudinally
Transitional
Smooth muscle. Contracts to expel urine from the bladder. Smooth muscle layers are arranged in multiple directions in the bladder whereas the layers in the ureter have more defined orientations.
Smooth muscle. Contracts to expel urine from the bladder. Smooth muscle layers are arranged in multiple directions in the bladder whereas the layers in the ureter have more defined orientations.
PCT
PCT
