Renal 2

Question 1

The epithelium around glomerular capillaries is modified into…

Answer 1

podocytes (leaving slits through which filtration takes place)

Question 2

mesangial cells

Answer 2

located between the capillaries that contract to alter blood flow (filtration)

Question 3

the renal corpuscle

Answer 3

a triple filtration barrier

Question 4

triple filtration barrier

Answer 4

-capillary endothelial cells
-basal lamina
podocyte endfeet

Question 5

capillary endothelial cells are ________________ so things can pass through.

Answer 5

fenestrated

Question 6

Which 3 pressures govern filtration from glomerular capillaries into the renal tubules?

Answer 6

• hydrostatic pressure
• colloid osmotic (oncotic) pressure
• Bowman’s capsule hydrostatic pressure

Question 7

hydrostatic pressure

Answer 7

of blood in the glomerular capillaries favours filtration; ~55mmHg

Question 8

colloid osmotic (oncotic) pressure

Answer 8

the pressure gradient due to the presence of plasma proteins and opposes filtration; ~30mmHg

Question 9

Bowman’s capsule hydrostatic pressure

Answer 9

fluid pressure that opposes filtration; ~15mmHg

Question 10

net filtration pressure is…

Answer 10

10mmHg (55-30-15)

Question 11

The volume of fluid that filters from the glomerular capillaries into the Bowman’s capsules per day?

Answer 11

180L/day

Question 12

The kidneys filter our entire plasma volume approximately…

Answer 12

60x/day

Question 13

What 2 factors influence glomerular filtration rate (GFR)?

Answer 13

net filtration pressure and filtration coefficient

Question 14

net filtration pressure

Answer 14

renal blood flow and blood pressure

Question 15

filtration coefficient

Answer 15

the surface area of the glomerular capillaries available for filtration and permeability of interface between capillaries and Bowman’s capsule

Question 16

GFR is primarily regulated by..

Answer 16

renal arterioles (afferent and efferent)

Question 17

Autoregulation maintains a constant GFR when mean arterial blood pressure is…

Answer 17

between 80 and 180 mmHg

Question 18

Renal blood flow’s resistance is determined by…

Answer 18

both the afferent and efferent arterioles (overall resistance)

Question 19

What two auto-regulatory mechanism maintain a relatively stable GFR in the face of normal blood pressure fluctuations

Answer 19

• myogenic response of the afferent arterioles

- tubuloglomerular feedback

Question 20

tubuloglomerular feedback

Answer 20

local control pathway in which fluid flow through the tubule portion of the nephron

Question 21

macula densa cells

Answer 21

sense distal tubule flow and release paracrine that affect afferent arteriole diameter

Question 22

granular cells

Answer 22

secrete renin, an enzyme involved in salt and water balance

Question 23

Flow __________ passed macula dense cells

Answer 23

increases

Question 24

Increased _____ has been shown to activate macula densa cells.

Answer 24

NaCl

Question 25

Sympathetic activation only really alters GFR under conditions of…

Answer 25

hemorrhage or severe dehydration

Question 26

What two hormones modulate arteriole resistance and filtration coefficient by acting on podocytes and/or mesangial cells?

Answer 26

angiotensin II (vasoconstrictor) and prostaglandins (vasodilator)