Renal Histology

Question 1

What are the Features of the Proximal collecting duct

Answer 1

- Thick Wall
	○ Cuboidal epithelium
	○ Brush border (microvilli)
	○ Very folded basolateral membrane
	○ Full of mitochondria

Question 2

What are the Features of the Distal collecting duct

Answer 2

• Has a larger lumen than proximal tubules
• No microvilli
• Many more mitochondria and ion pumps than the proximal and is involved in further ion reabssorption
• Has a specialised region called the Macula densa

Question 3

What are the features of the Loop of Henle

Answer 3

• Includes a thin and thick region of the wall
• The thhin region is only permeable to water and only water moves out. Thin region has a simple squamous coating.
• The thick regions will modulate the salt concentration and establish a osmolarity gradient to further promote osmosis and concentrate urine

Question 4

What are the features of the Collecting Duct

Answer 4

• Simple cuboidal epithelium that become more columnar along the duct
• Large Lumen
• Empty into renal pelvis and calyces
• Impermeable to waer, except when activated by ADH and aquaporins are inserted into epithelium.

Question 5

What is the epithelium of the ureters and the Bladder and the urethra

Answer 5

Is transitional epithelium however in the last region of the urethra is stratified epithelium

Question 6

What cells comprise the Juxtaglomeruli complex

Answer 6

Macula densa in DCT, Juxtamedullary cells in the Afferen arterioles and extraglomeruli mesangial cells

Question 7

Function of Macula ensa

Answer 7

Detects blood pressure indirectly by Na+ ions

Question 8

Function of Juxtamedullary cells

Answer 8

Release Renin

Question 9

Function of extraglomruli mesangial cells

Answer 9

Detect BP via stretch of mecanoreceptors

Question 10

Four functions of ATII

Answer 10

ADH release, alddosterone release from adrenal cortex, acts directly on renal tubules and vasoconstricton

Question 11

Causes of Pre renal failure

Answer 11

Hypotension, hypertension and toxins

Question 12

Causes of Post renal failure

Answer 12

Bloackage of ureters, bladder or urethra

Question 13

Causes of intrarenal renal failure

Answer 13

ATN, AIN glomerulonephritis, inflammation,

Question 14

Consequences of chronic renal failure

Answer 14

Decreased EPO, Vitamin D (ricketts), increased BP, High K+ (AF), Acidosis and Na+ (high with glomeruli, low with tubular)

Question 15

Signs of chronic renal failure

Answer 15

Fatigue (Aneamia), LOA, skin pigmentation and confusion (toxins in blood)

Question 16

What are the componants of the BM in the kidney

Answer 16

Podocyte foot procesess, collagen IV, fenestrations in endothelium and proteins such as Nephrin, Podrin and Neph 1/2 which all lead to a negative charge

Question 17

WHat are the to types of glomeruli

Answer 17

Juxtamedullary (15%) (Medulla) and cortical (85%)