Renal Physiology

Question 1

net fluid flow equation?

Answer 1

=Kf [(Pc −Pi)−ς(πc −πi)]

Question 2

What does Kf stand for?

Answer 2

permeability of capillary to fluid

Question 3

What does ς stand for?

Answer 3

permeability of capillary to protein

Question 4

When is Capillary Pressure increased?

Answer 4

HF

Question 5

When is plasma protein decreased (πc)?

Answer 5

Nephrotic syndrome and liver failure (cirrhoris)

Question 6

When is Capillary permeability increased?

Answer 6

toxins, infections, burns (TIBs and Bulls)

Question 7

When is interstitial fluid colloid osmotic pressure (πi) increased

Answer 7

Lymphatic Blockage

Question 8

Increased Capillary Pressure, Plasma Protein decrease, Capillary permeability increase, interstitial fluid colloid osmotic pressure (πi) increase all cause?

Answer 8

Pulm. edema

Question 9

What is the 60–40–20 rule?

Answer 9

60% total body water ƒ
40% ICF
ƒ20% ECF

Question 10

Plasma volume is measured by?

Answer 10

Albumin

Question 11

Extracellular is measured by?

Answer 11

Inulin

Question 12

GFR barrier is composed of?

Answer 12

Fenestrated capillary endothelium (size
barrier)
ƒ
Fused basement membrane with heparan
sulfate (negative charge barrier)
ƒ
Epithelial layer consisting of podocyte foot
processes

Question 13

Cx > GFR

Answer 13

net tubular secretion of X

Question 14

Renal Clearance formula

Answer 14

Plasma Conc. * Flow=Urine Conc. *Flow

FIltered Load=Exretion Rate

Question 15

For GFR and Inulin, Formula is?

Answer 15

GFR = Uinulin × V/Pinulin = Cinulin

= Kf [(PGC – PBS) – (πGC – πBS)]

Where BS=0

Question 16

Normal GFR is about?

Answer 16

100

Question 17

RPF can be best estimated by? GFR?

Answer 17

para-aminohippuric acid (PAH)

GFR=creatinine

Question 18

Why is para-aminohippuric acid (PAH) best representation of RPF?

Answer 18

because it is both filtered and secreted in the proximal collecting tubule (PCT), resulting in near 100% excretion of all PAH entering kidney.

Question 19

Formula for RBF?

Answer 19

RBF=RPF/(1-HCT)

Question 20

RPF underestimates real RPF by?

Answer 20

10%

Question 21

FF=?

Answer 21

GFR/RPF

Question 22

Filtered Load=?(1st portion of the GFR equation)

Answer 22

GFR*Plasma conc.

Question 23

What dilates the afferent arterioles?

Answer 23

PGE

Question 24

What constricts the efferent arterioles?

Answer 24

AT2

Question 25

With Afferent Arterioles constriction, what happens to the GFR and RPF and FF?

Answer 25

Decreased GFR, RPF; Nothing with FF

Question 26

With Efferent Arterioles constriction, what happens to the GFR and RPF and FF?

Answer 26

Increased GFR, Decreased RPF, FF=>increases

Question 27

Decreasing the plasma protein concentration (Cirrhoris) does what to the GFR and FF?

Answer 27

Increasing GFR, FF

Question 28

Constricting the ureters does what to the GFR and FF?

Answer 28

Decreases GFR, FF

Question 29

When do you first see glucose in the urine?

Answer 29

200 mg/dL

Question 30

WHen are all glucose transporters at TM?

Answer 30

375mg

Question 31

Other than DM, where can you see increased glucose concentrations being excreted?

Answer 31

Pregnancy

Question 32

Hartnup disease? MOA? Genetics?

Answer 32

autosomal recessive. Deficiency of neutral amino acid (tryptophan) transporters in proximal renal tubular cells and on enterocyte=>pellagra-like symptoms.