Glomerular Structure and Function

Question 1

At what vertebral level do the kidneys lie in?

Answer 1

T12 to L3

Question 2

Which kidney lies lower than the other?

Answer 2

Right kidney, because of the liver

Question 3

The kidneys are approximately what length?

Answer 3

The length of three vertebrae

Question 4

From most deep to superficial, what are the four layers of fascia/fat surrounding the kidneys?

Answer 4

1. Renal capsule (deep)
2. Perirenal fat
3. Renal fascia
4. Pararenal fat (superficial)

Question 5

The renal parenchyma can be divided into two main structures, what are they?

Answer 5

Outer cortex

Inner medulla

Question 6

The medulla of the kidney is divided into triangular shapes called?

Answer 6

Renal pyramids

Question 7

The apex of the renal pyramid is called?

Answer 7

Renal papilla

Question 8

What structure collects urine from the renal papilla - and what does it drain into finally?

Answer 8

Minor calyx, draining into major calices

Question 9

The kidneys are supplied by what arteries? Where do these arteries arise from?

Answer 9

Renal arteries, from abdominal aorta

Question 10

Describe the pattern of division of the renal arteries as it supplies the renal parenchyma

Answer 10

Renal artery -> Segmental artery -> Interlobar artery -> Arcuate artery -> Interlobular artery (90 degrees from arcuate artery) -> Afferent arterioles -> Glomerulus

Question 11

The kidneys are drained by what veins? What do they then drain in to?

Answer 11

Renal veins, draining into inferior vena cava

Question 12

Why is the left renal vein longer than the right renal vein?

Answer 12

Because the inferior vena cava lies to the right hand side

Question 13

What structures are more anterior (front) - the inferior vena cava or the abdominal aorta - as it enters the kidneys?

Answer 13

Inferior vena cava (anterior)

Question 14

Lymph from the kidneys drain into…?

Answer 14

Lateral aortic nodes

Question 15

What are the two types of nephrons in the kidney, and how are they different?

Answer 15

Cortical nephrons - short Loops of Henle

Juxtomedullary nephrons - long Loops of Henle

Question 16

What are the three cellular layers within the Glomerulus?

Answer 16

Fenestrated endothelium
Basement membrane
Epithelium with podocytes

Question 17

The Juxtaglomerulus Apparatus is in close contact with the ______ Convoluted Tubule

Answer 17

Distal

Question 18

The Juxtaglomerulus Appatarus is comprised of three distinct structures - what are they?

Answer 18

Macula Densa
Granular cells
Extraglomerular mesangial cells

Question 19

What is normal GFR in humans?

Answer 19

125ml / min

Question 20

Cations less than 68kDa are restricted from passing through the glomerular filtration barrier, true or false?

Answer 20

False, anions are

Question 21

How much blood is filtered by the kidneys per min?

Answer 21

1.2 litres

Question 22

To increase GFR, how would the afferent / efferent arterioles need to change?

Answer 22

Afferent = dilate
Efferent = constrict

Question 23

Give 4 examples of substances which can increase GFR

Answer 23

Prostaglandins
Kinins
Dopamine
NO

Question 24

Give 3 examples of substances which can decrease GFR

Answer 24

High dose Angiotensin II
Noradrenaline
ADH

Question 25

Angiotensin II has what effect on the afferent and efferent arterioles of the kidney?

Answer 25

In low dose, efferent arteriole constriction In high dose, afferent arteriole constriction

Question 26

Angiotensin II blockade has what effect on the efferent arteriole?

Answer 26

Dilatation

Question 27

What are the two types of mesangial cells?

Answer 27

Extraglomerular | Intraglomerular

Question 28

Angiotensinogen is released by what?

Answer 28

Liver

Question 29

In response to angiotensinogen release, what happens?

Answer 29

Renin is released by the kidneys

Question 30

Angiotensinogen + Renin = ?

Answer 30

Angiotensin I

Question 31

Where is ACE released from? What does it do?

Answer 31

Kidney and lung endothelia, converts Angiotensin I to Angiotensin II

Question 32

What is the role of Angiotensin II?

Answer 32

Stimulates aldosterone release from the kidneys, to increase reabsorption of Na+ and increasing BP Aldosterone also depletes K+ levels Angiotensin II also causes vasoconstriction in renal arterioles to increase BP further

Question 33

What are some problems with using Serum creatinine as a measure for GFR?

Answer 33

1. It is actively secreted by the tubules (up to 15%) 2. Insensitive as a marker for early kidney disease 3. It is affected by muscle mass 4. Affected by certain drugs