CVPR Week 7: Glomerular Filtration

Question 1

Objectives

Answer 1

Question 2

Identify

Answer 2

Question 3

Identiify

Answer 3

Question 4

Location of the glomeruli

Answer 4

Question 5

Identify

Answer 5

Question 6

What gets through glomerular filtration?

Ultrafiltrate composition

Answer 6

• Proteins and cells excluded at the endothelium
• Electrolytes and small molecules are filtered
• Negatively charged barrier inhibits filtration of negatively charged substances
• Filtrate formed at a rate of 100 to 140

Question 7

Glomerular filtration rate

Answer 7

filtrate formed at a rate of 100 to 140

Question 8

Filtrate =

Answer 8

Plasma - proteins (and protein-bound substances)

Question 9

Average filtrate volume

Answer 9

125 mL/min

180 L/day

Question 10

What percent of filtrate is reabsorbed?

Answer 10

99% of filtrate is reabsorbed

Question 11

Starling’s Forces of filtration

Answer 11

Question 12

~ Glomerular afferent capillary pressure

Answer 12

60 mmHg

Question 13

~ Glomerular efferent capillary pressure

Answer 13

60 mmHg

Question 14

~ Glomerular capillary pressure

afferent to efferent

Answer 14

stays at 60 mmHg

Question 15

~ Glomerular afferent oncotic pressure

Answer 15

-25 mmHg

Question 16

~ Glomerular efferent oncotic pressure

Answer 16

-35 mmHg

Question 17

~ Glomerular oncotic pressure from afferent to efferent

Answer 17

-25 afferent to -35 efferent

so - 10 mmHg difference

Question 18

~ Bowman’s space afferent oncotic pressure

Answer 18

0 mmHg

Question 19

~ Bowman’s space efferent oncotic pressure

Answer 19

0 mmHg

Question 20

~ Bowman’s space oncotic pressure

afferent to efferent

Answer 20

stays at 0 mmHg

Question 21

~ Bowman’s space afferent hydrostatic pressure

Answer 21

• 15 mmHg

Question 22

~ Bowman’s space efferent hydrostatic pressure

Answer 22

-15 mmHg

Question 23

~ Bowman’s space hydrostatic pressure from afferent to efferent

Answer 23

stays at -15 mmHg

Question 24

Ultrafiltrate pressure in afferent end

Answer 24

20 mmHg

Question 25

Ultrafiltrate pressure in efferent end

Answer 25

10 mmHg

Question 26

What is the filtration coefficient?

Answer 26

(K_f)

It is the measure of membrane permeability

Question 27

Normal GFB values

Answer 27

12.5 mL/min/mmHg

Question 28

What regulates K_f?

Answer 28

• Mesangial cells regulate K_f
• hormones and disease can alter K_f including mutations of nephrin, glycocalyx loss and complement-mediated injury

Question 30

Mechanisms that can alter K_f

Answer 30

• mutations of nephrin
• glycocalyx loss
• complement-mediated injury

Question 31

How do Mesangial cells regulate K_f?

Answer 31

Mesangial cell contraction decreases K_f

Question 32

What is the normal oncotic pressure in Bowman’s space?

Answer 32

0 mmHg

Question 33

Glomerular filtration equation

Answer 33

Question 34

Starling forces in the glomerular capillaries from afferent to efferent

Answer 34

Question 35

Glomerular capillary pressure and GFR

Answer 35

Question 36

Identify

Answer 36

Question 37

What are these?

Answer 37

Question 38

Angiotensin II and GFR

Answer 38

Question 39

Changes in GFR due to a SMALL increase in Angiotensin II

Answer 39

Question 40

Changes in GFR due to a LARGE increase in Angiotensin II

Answer 40

Question 41

Describe the Macula Densa regulation of Renin secretion and ECF

Answer 41

Question 42

long and short loops of Macula Densa Regulation of Renin secretion and ECF

Answer 42

Question 43

Clearance units

Answer 43

mL plasma cleared/min

Question 44

Clearance equation

Answer 44

Question 45

How to calculate GFR

Answer 45

Question 46

GFR final equation

Answer 46

Question 47

Inulin factor

Answer 47

Question 48

How to estimate GFR?

Answer 48

Question 49

How to estimate RPF?

Answer 49

Question 50

RBF AKA

Answer 50

Renal blood flow

Question 51

RBF equation

Answer 51

Question 52

FF AKA

Answer 52

Filtration Fraction

Question 53

FF equation

Answer 53

Question 54

Question 1