Renal Phys 2

Question 1

How many nephrons in the human kidney?

Answer 1

1,000,000

Question 2

How many nephrons in cat kidney?

Answer 2

200,000

Question 3

How many nephrons in dog kidney?

Answer 3

500,000

Question 4

Do pigs and cattle have more or less nephrons than a human?

Answer 4

more

Question 5

Fractional Excretion Equation

Answer 5

excretion load divided by filtered load, times 100

Question 6

What is better - low or high fractional excretion?

Answer 6

low - this means the tubules are working well

Question 7

Cause of Proteinuria or Hypoproteinemia?

Answer 7

glomerular injury or disease

Question 8

Normal BUN/Creatinine Ratio

Answer 8

20

Question 9

BUN/Creatinine less than normal?

Answer 9

acute renal disease

Question 10

BUN/Creatinine higher than normal?

Answer 10

pre-renal disease (BUN increases faster than creatinine)

Question 11

Clearance Equation

Answer 11

Question 12

Freely Filtered

Answer 12

concentration in the Bowman’s space equals the concentration in the plasma

Question 13

clearance

Answer 13

relationship between amt of substance delivered in the kidney to the amount of substance excreted in the urine

Question 14

Why is muscle mass important when considering creatinine levels?

Answer 14

creatinine is a breakdown product of muscle, and so animals with higher muscle mass will have higher serum creatinine

ex: 1.4 could be normal for healthy muscular dog but indicate renal problems in an old muscle wasted dog

Question 15

By what percent does creatinine clearance overestimate GFR?

Answer 15

10%

Question 16

Do you find inulin in animals?

Answer 16

no, it is a plant polysaccharide - has to be infused in order to test flow rate

Question 17

Relationship between GFR and serum creatinine?

Answer 17

inverse (as GFR decreases blood creatinine increases)

Question 18

Creatinine Levels and Diagnosing Renal Disease

Answer 18

very small changes in creatinine with big decreases in GR, means not great at detecting early kidney disease because the change is so subtle

Question 19

Normal serum creatinine in dogs? cats?

Answer 19

Dogs = 1.4 mg/dL or less
Cats = 1.6 mg/dL or less

Question 20

Azotemia

Answer 20

elevation of BUN

Question 21

BUN

Answer 21

blood urea nitrogen

Question 22

Para-aminohippurate (PAH)

Answer 22

used to measure RPF (renal plasma flow) because it is completely removed from blood in the kidneys so its clearance is equal to RPF

Question 23

Equation for Effective RPF

Answer 23

concentration of PAH

Question 24

What percent of renal blood flow (RBF) does not supply the glomeruli?

Answer 24

10% (supplies the fat and nerve cells of the kidney)

Question 25

Equation for True RPF

Answer 25

effective RPF divided by 0.9

Question 26

Equation for RBF (Renal Fraction)

Answer 26

Question 27

Clearance Ratio

Answer 27

CR = 1, substance is being filtered (ex: creatinine, inulin) CR < 1, substance is reabsorbed (ex: urea, AAs, bicarbonate) CR > 1, substance is secreted (ex: PAH)