Flashcards in Kidney Function 1 Deck (48):
0
3 things to take away from the lecture:
autoregulation
clearance
macula densa
1
4 main functions of kidney
1. water sodium balance
2. ion control, K+, CA2+, Mg2+
3. acid-base balance
4. excretion
2
is acid-base balance only done by kidney?
nope. in conjunction with lungs
3
what happens if ion concentrations get out of hand?
could be deadly and sudden death from nerve, muscle, brain damage
4
uraemia is what?
chronic renal failure due to a general plethora of products
5
what does Renin do?
hormone what regulates BP and Na+
6
Vitamin D3 has homey hydroxyl compared to calciferol?
3OH vs. 1OH
7
what does formation of concentrated urine do? what is min vs. max?
excrete toxins and waste
30mOsm/L - 1200 mOsm/L
8
what is formation of dilute urine do?
remove excess water
9
85% of glomeruli are what?
superficial cortical glomeruli SCGs
10
what are JM glomeruli?
juxtamedullary glomeruli: deep penetrating loops of HEnle into medula
11
SCGs are what?
superficial cortical glomeruli with shallow penetrance of loops of Henle
12
more loops of henle deeper or superficially?
superficially due to 85% of glomeruli being SCGs
13
juxtamedullary glomeruli account for concentration gradient, where is it higher? lower?
300 at superficial
1200 in deepest papilla part of medulla
14
Expand these acronyms: PCT, tDLH, tALH, TAL, DT, CD
proximal convoluted tubule
thin descending loop of henle
thin ascending loop of henle
Thick ascending loop of henle
Distal Tubule
collecting duct
15
where does the TAL attach to parent glomerulus?
end of TAL attaches between efferent and afferent arteriole
16
how many nephrons per kidney?
1 million
17
how many L out of daily 180L of filtrate goes back into efferent arteriole?
178L
18
what is renal blood flow per minute? per kidney?
1L/min, 500ml per kidney
19
filtration fraction is?
20% or 0.2
20
what is normal haematocrit?
40
21
if renal plasma flow is 600ml, what is total GFR? GFR per kidney?
total GFR is 125ml or 60ml per kidney
22
how much cardiac output needed to run the renal filtration system?
20%
23
describe the efferent renal arteriole
artery to capillary to artery to capillary to vein
24
Na+ or K+ more important for secretion?
K+
25
macula densa cells close to the arteriole make what? does what?
Renin which ends up vasoconstricting
26
macula densa detect Na+ feeback via paracrine mediators such as? what does it adjust?
prostaglandins and adenosine
alters afferent arteriole tone to adjust resistance and keep glomerulus constant at 50mmHg
27
epithelial granular cells near afferent arteriole make what?
Renin
28
What is myogenic response/reflex?
if too much stretch on afferent arteriole, is contracts to mitigate any dilating force
29
Creatinine level is equated roughly the same as the?
GFR
30
3 components of filtration in Bowman's Capsule?
filtration slits
basal lamina
fenestrations
31
what is hallmark of advanced diabetes?
albumin in the urine as the basal lamina degenerate, lose negative charge and ability to repel
32
what is normal hydrostatic pressure in glomerular capillary?
50mmHg
33
what is normal hydrostatic pressure in Bowman's capsule?
10mmHg
34
what is normal oncotic pressure in glomerular capillary?
25-40mmHg
35
what is normal oncotic pressure in Bowman's capsule?
0mmHg
36
what is the normal net filtration pressure across bowman's capsule?
10mmHg into nephron
37
Angiotension II preferentially constricts which arteriole?
efferent arteriole
38
which arteriole does autoregulation occur at?
afferent arteriole
39
BP can vary between what and still maintain normal GFR?
80-180mm Hg
40
what happens if low sodium? how do you maintain BP?
macula densa detects, triggers Renin to increase BP via unknown mechanism
41
what are the 3 drivers of renin release?
sympathetic
decreased BP
decreased NaCl
42
Renin affects afferent or efferent?
efferent
43
what happens if Na+ too high?
releases thromboxane and adenosine which constricts afferent
44
Renal clearance of a substance equation is?
Urine Volume / plasma concentration
45
Inulin is a marker for what?
GFR
46
how much Glucose clearance per minute in nephron?
0mL/min
47