Renal Blood Flow and Glomerular Filtrate I

Question 1

What effect does constriction of the efferent arteriole have on GF?

Answer 1

Increases glomerular filtration

Question 2

What is the best substance for measuring GFR and what is actually used clinically?

Answer 2

Inulin is the best

Creatinine is used

Question 3

What does creatinine levels tell?

Answer 3

The glomerulus filtration rate (GFR)

Question 4

How is inulin excretion related to its concentration in the plasma?

Answer 4

It is directly proportional

Question 5

As plasma creatinine increases what occurs to excreted creatinine and why?

Answer 5

Decreases, it means GFR decreased thus the creatinine in the blood is not filtered out and increases (less excreted)

Question 6

What affects selective permeability in the glomerulus?

Answer 6

Molecular weight

Effective molecular radius

Question 7

Why can proteins be found in the urine during a kidney infection?

Answer 7

The podocytes carry a negative charge, during an infection they may become damaged and lose their charge allowing negative proteins through

Question 8

What is filtration fraction?

Answer 8

The volume of filtrate that forms from a given volume of plasma entering the glomerulus

Question 9

What is the formula for FF?

Answer 9

GFR/RPF

Question 10

Renal vessel vasoconstrictors:

Answer 10

Sympathetic nerves
Angiotensin II
Endothelin

Question 11

Renal vessels vasodilators:

Answer 11

PGE2
PGI2
Nitric oxide
Bradykinin
Dopamine
Atrial natriuretic peptide

Question 12

What occurs to FF with increased afferent flow?

Answer 12

Decreases (doesn’t have the ability to filter that much volume efficiently)

Question 13

What occurs to GFR with constriction of afferent arteriole?

Answer 13

Decreases

Question 14

What is RPF?

Answer 14

Renal plasma flow: amount of plasma delivered to the kidneys per unit of time

Question 15

What are the peritubular capillaries?

Answer 15

Follow the nephron tubules (branch from efferent)

Question 16

Three parameters to calculate the clearance of solute X:

Answer 16

1. ) Concentration of X in urine
2. ) Volume of urine formed in a given time
3. ) Concentration of X in systemic blood plasma

Question 17

What is special about PAH (p-aminohippuric acid)?

Answer 17

It is completely removed in one pass through the kidney so it is a clinical test to measure renal plasma flow

Question 18

Four factors that modulate RBF and GFR?

Answer 18

1. ) Renin-angiotensin-aldosterone cascade
2. ) Sympathetic nerves
3. ) Arginine vasopressin (ADH)
4. ) Atrial natriuretic factor