Renal 1

Question 1

Formula for excreted amount

Answer 1

Filtered - reabsorbed + secreted.

Question 2

Peritubular capillary

Answer 2

Capillary following the efferent arteriole

Question 3

Glomerular filtration rate

Answer 3

Amount that enters bowman’s space, 125mL.

Question 4

Renal plasma flow

Answer 4

Amount of blood passing through the glomerular capillary, 625mL/min

Question 5

Filtration fraction

Answer 5

GFR/RPF, 0.2.

Question 6

Podocyte

Answer 6

Modified epithelial cells that are involved in the filtration barrier.

Question 7

Filtration barrier layers (3)

Answer 7

Fenestrations
Basement membrane
Podocyte slit pores

Question 8

What properties determine glomerular filter ability

Answer 8

Size and Charge
18Å > 45Å
positive > negative

Question 9

Proteins do/do not filter into bowman’s space

Answer 9

DO NOT! BAD THING IF SO.

Question 10

GFR is the consequence of

Answer 10

ultrafiltration coefficient and net filtration pressure.

Question 11

Hydrostatic pressure (P)

Answer 11

Limited containers cause pressure

Question 12

Colloid pressure

Answer 12

Osmotic pressure due to many proteins in one fluid.

Question 13

Forces favouring filtration

Answer 13

Pgc
πbs

Question 14

Forces opposing filtration

Answer 14

Pbs
πgc

Question 15

GFR =

Answer 15

Kf x (Pgc - Pbs - πgc)

Question 16

Positive pressure goes from the ____ into the _____.

Answer 16

Glomerular capillary to the bowman’s space

Question 17

Most important pressure

Answer 17

Pgc

Question 18

Lower Pnet at the efferent end? why?

Answer 18

Protein concentration has increased, counter pressure goes up for πgc.

Question 19

Constriction of the afferent

Answer 19

Blood flow through decreases.
Easily leaves glomerular, blood build up decreasing, pressure goes down.
GFR decreases.

Question 20

Constriction of the efferent

Answer 20

Blood builds up in the glomerulus, causing the pressure to increase. GFR increases.

Question 21

Dilation of the afferent

Answer 21

More blood flows in, leaves at the same rate causing it to build up. Pressure increases, and so does GFR.

Question 22

Dilation of the efferent

Answer 22

Easier for blood to leave causing a decrease in blood in the glomerulus. This decreases pressure, decreasing GFR.

Question 23

Natriuretic peptides as a vasodilator and constrictor in increasing urine production

Answer 23

Dilates afferent (increase GFR), constricts efferent (increase GFR).

Question 24

Autoregulation of GFR and RBF (2) ways

Answer 24

1. myogenic mechanism
2. tubulogenic feedback

Question 25

Myogenic mechanism

Answer 25

Smooth muscle stretch stimulates SSCa2+ channels causing contraction, increasing afferent arteriolar resistance.

Question 26

Tubulogenic feedback mechanism

Answer 26

Increased GFR causing nephronic NACl to increase. Macula densa senses using JGA cells, causing afferent constriction.

Question 27

Chronic kidney disease

Answer 27

Progressive loss of kidney function decreases GFR and urinary production down from 125mL/min.

Question 28

Measuring GFR via inulin clearance

Answer 28

Inject people GFR = (Uin x V) / Pin) 1mg/mL in plasma, 125mg/mL in urine as water is reabsorbed.

Question 29

Measuring GFR via creatinine clearance

Answer 29

FIltered well by kidneys Clearance is very similar to GFR clearance = (Ucr x V) / Pcr

Question 30

Plasma creatinine to clinically measure GFR

Answer 30

Creatinine clearance decreases as kidney function decreases, causing build up in plasma