Physio Exam 3 Renal 1

Front 1

Whats the resting renal blood flow?..this volume corresponds to what portion of cardiac output?

Back 1

1.25 L/min
25%

Front 2

Permeability tp water of descending loop of Henle

Back 2

permeable to water

Front 3

Which tubules are impermeable to water

Back 3

Thin and thick ascending tubules, distal convoluted tubules and collecting tubules

Front 4

Superficial nephrons characteristics

Back 4

Superficial Cortical
Midcortical
Glomerulus in outer cortex
Short Loops of Henle
Cortical
Outer Medulla
85% of Total Nephrons
Excretory and Regulatory

Front 5

Juxtamedullary Nephrons characteristics

Back 5

Glomerulus Deep
Corticomedullary border
Long loops of Henle
Subserved by Vasa Recta
15% of Total Nephrons
Dilution and Concentration

Front 6

Afferent arterioles come off

Back 6

of the interlobar arteries

Front 7

Afferent arterioles give rise to

Back 7

glomerulus

Front 8

Efferent arterioles give rise to

Back 8

peritubular capillary bed

Front 9

Equilibration of solutes in the ascending and descending tubes due to

Back 9

Vasarecta

Front 10

Bowman’s Capsule

Back 10

cup like sac at
the beginning of the tubular component
of a nephron

Front 11

Glomerulus

Back 11

Ball of capillaries within
Bowman’s Capsule

Front 12

Juxtaglomerular Apparatus

Back 12

Includes
structures of Bowman’s Capsule, the
Glomerulus, and regulatory components
such as the renin secreting juxta-
glomerular cells, epithelial cells forming
the macula densa of the nephron’s
thick ascending limb, and mesangial
cells in the interstitium.

Front 13

Specialized cells which assist iin contraction of glomerulus for filtration

Back 13

mesangial cells

Front 14

Whats forms the ultrafiltrate?

Back 14

A fraction of the Solute and Fluid
in the Plasma that enters the
glomerulus f

Front 15

Where does the ultra filtrate enter?

Back 15

Bowman's spance

Front 16

The three general renal functions are

Back 16

Glomerular filtration
Tubular Secretion
Tubular reabsorption

Front 17

Glomerular filtration refers to

Back 17

Substances that get filtered out of capillaries into Bowman's capsule and then become insipient urine

Front 18

Renal clearance refers to

Back 18

the rate at which all of substance X is removed from
plasma and excreted in urine (volume/unit time) where substance X must be neither synthesized nor metabolized

Front 19

Equation for renal clearance

Back 19

X=Cx Urine flow (V) x [X] in urine/[X] in plasma

Front 20

The arterial blood concentration for substance X is 50 mg/ml.
the urine concentration is 100 mg/ml. and the urine flow rate is
0.5 ml/min. What is the clearance rate for substance x

Back 20

Cx = 0.5 ml/min. X 100 mg/ml = 1 ml/min.
50 mg/ml

Front 21

Glomerular filtration requirements

Back 21

Not synthesized or metabolized
Freely Filtered
Not secreted or reabsorbed

Front 22

Renal Plasma Flow requirements

Back 22

Not synthesized or metabolized
Freely Filtered
Does not alter RPF
100% Filtered or Secreted

Front 23

Glomerular Filtration Rate can be measured by

Back 23

Clearance of Inulin or Creatine

Front 24

Renal Plasma Flow referes to

Back 24

para-aminohippuric acid (PAH)

Front 25

released from skeletal
muscle during metabolism. Works
well because it is produced at a
relatively steady rate dependent on
muscle mass.

Back 25

Creatinine

Front 26

polyfructose of MW 5,000
must be infused to assess GFR. Measures
“true” GFR

Back 26

Inulin

Front 27

GFR equation

Back 27

GFR= [U]inulin (V)/[P]inulin

Front 28

When is Creatine Not useful to measure GFR?

Back 28

during kidney failure

Front 29

Pros of using creatine to measure GFR

Back 29

Easy to measure in blood
Inverse relationship between PCR
and GFR. {Ccr = (Ucr )(V)/Pcr}

Front 30

Cons of using creatine to measyre GFR

Back 30

Must have large drop in GFR before
increases in PCR are significant
At low GFRs (below 40L/day)
significant creatinine is secreted

Front 31

Blood Urea Nitrogen is a
consequence of liver protein catabolism. It is freely
filtered and large elevations from normal values
(7 – 20 mg/dL) are seen with

Back 31

withdecreases in GFR
due to renal failure.

Front 32

because urea is
reabsorbed, secreted, and excretion depends on urine flow rate, elevations in BUN can be seen
with normal kidney function. A BUN/creatinine ratio greater than 20 is suggestive of

Back 32

a pre-renal
mechanism (dehydration)

Front 33

PAH is used to determine RBL because

Back 33

Freely Filtered
Not metabolized
Does not alter RPF
Not reabsorbed
Fully Secreted

Front 34

Renal plasma flow equarion

Back 34

RPF=[U]PAF (V)/P[PAF]
or
RPF/1-hematocrit

Front 35

Effective RPF; PAH clearance underestimates RPF by ~10 because

Back 35

about 10%of blood that enters the system does go to glomeruli

Front 36

PAH infusion to achieve steady plasma
levels. First pass clearance approaches
100%. Plasma concentration must not

Back 36

saturation of transporters (~20 mg/dL

Front 37

EWhat happens when something gets above 20?

Back 37

ttehre a ponint in which transporters saturate and filtration.

Front 38

Filtration Fraction is

Back 38

the fraction of the plasma filtered by the glomerulus
and passing into the tubules

Front 39

The Filtration Fraction equation

Back 39

GFR/RPF=Cinulin/CPAH)

Front 40

The Filtration Fraction will increase with a decrease
in RPF if GFR is held constant (ex

Back 40

renal artery stenosis

Front 41

Filtration Fraction will decrease with a decrease in GFR
If RPF is held constant (ex

Back 41

systemic lupus erythematosus

Front 42

Clearance Ratio

Back 42

Assessment of net Reabsorption and Secretion
Assessment based on comparison to Cin
CX > Cin net secretion (Clearance Ratio greater than 1)
CX < Cin net reabsorption (Clearance Ratio less than 1)

Front 43

Clearance ratio euqation

Back 43

Cx/insulin