Renal Flashcards
(107 cards)
1
Q
What is the pathway of blood supply to the kidleys?
A
Renal Artery, Afferent Arterioles, Glomerular Capillaries, Efferent Arterioles, Peritubular Capillaries, Renal vein
2
Q
What is the function of the Glomerulus?
A
Filtration membrane across capillaries: provides filtration of blood cells and most proteins
3
Q
What are fenestrations?
A
large pores in endothelial cells
4
Q
What are Mesangial cells?
A
Contractile cells located around glomerulus that help regulate how much surface area is available for glomerular filtration-when contracting the surface area for filtration decreases
5
Q
What is the function of Juxtaglomerular apparatus?
A
helps regulate blood pressure
6
Q
What are the functions of the kidney and urinary system?
A
excretion of metabolic waste products and foreign chemicals, regulate plasma volume, and blood pressure, regulate osmolarity and electrolytes, Vit. D synthesis, Erythropoietin synthesis, acid base balance, and gluconeogenesis
7
Q
The efferent arteriole is ____ in diameter than the afferent arteriole in the kidney?
A
smaller
8
Q
Resistance to blood outflow is high which _____ blood pressure within glomerulus?
A
increases
9
Q
Capsular oncotic pressure is typically what?
A
zero, unless there is a pathological condition present
10
Q
GFR=
A
Kf * net filtration pressure
11
Q
what does Kf equal?
A
12.5
12
Q
Constriction of afferent arteriole ____ blood flow into glomerulus
A
decreases
13
Q
Constriction of afferent arteriole _____ blood hydrostatic pressure
A
decreases
14
Q
Constriction of afferent arteriole ___ GFR
A
decreases
15
Q
Constriction of efferent arteriole ___
A
outflow of blood from glomerulus
16
Q
Constriction of efferent arteriole ___ blood hydrostatic pressure in glomerulus
A
increases
17
Q
Constriction of efferent arteriole ____ GFR
A
increases
18
Q
SNS causes ____ of afferent and efferent arterioles
A
vasoconstriction
19
Q
What effect does ANGII have on the glomerulus?
A
vasoconstricts efferent arteriole
20
Q
What effect does ANP have on the glomerulus?
A
dilates afferent arterioles
21
Q
what effect does Norepi and Epi have on the glomerulus?
A
vasoconstricts afferent and efferent arterioles
22
Q
what effect does Nitric oxide have on the glomerulus?
A
causes vasodilation of afferent arteriole
23
Q
what effect do prostaglandins have on the glomerulus?
A
vasodilates afferent arteriole
24
Q
what effect does endothelin have on the glomerulus?
A
vasoconstricts afferent arteriole
25
How would arteriosclerosis in the afferent arteriole decrease GFR?
decrease glomerular hydrostatic pressure
26
How would a kidney stone in a ureter decrease GFR?
increase capsular hydrostatic pressure
27
What effect does ANGII have on GFR?
Increase
28
What effect does ANP have on GFR?
Increase
29
What effect do prostaglandins have on GFR?
increase
30
what effect does strong SNS stimulation have on GFR?
Decrease
31
Secretion of H+ ions is essential for reabsorption of what?
HCO3-
32
What catalyzes H2CO3- into water and CO2?
carbonic anhydrase
33
What would happen to the HCO3- reabsorption in the PCT if the sodium/potassium ATPase in those cells was inhibited?
It would decrease because there will be a loss of the ion gradient to keep the H+ ions flowing with the sodium Hydrogen anti-porter
34
Where in the kidney pathway does urine become hypotonic?
ascending LOH and early DCT
35
How can inhibition of the Na/Cl/K symporter lead to hypomagnesemia?
This will block the K gradient building in the lumen which will lead to less positive pressure there to drive the Mg back into the blood.
36
If you increase sodium delivery you will increase potassium ____
secretion
37
A carbonic anhydrase inhibitor acting in the CD will cause alkalosis or acidosis?
Acidosis
38
Furosemide will have what effect on K+ secretion in the CD?
Increase; sodium reabsorption is inhibited in the LOH so there is more sodium in the filtrate and when it reaches the CD at that concentration a lot more sodium reabsorption occurs
39
Hyperaldosteronism can cause (hyper or hypokalemia) and (acidosis or alkalosis)
Hypokalemia and alkalosis
40
SNS stimulation and a drop in renal perfusion will ____ stimulation of renin
increase
41
Hyperkalemia can also _____ the aldosterone secretion
stimulate
42
What does ADH do to reabsorption?
increase reabsorption of water
43
What does ANGII do to reabsorption?
Increases Na and water reabsorption and secretion of H in PCT by stimulating Na/H anti-porters
44
What does Aldosterone do to reabsorption?
stimulates release of aldosterone form adrenal gland. Increases Na reabsorption and secretion of K in principle cells. Stimulates H from intercalated cells.
45
What does ANP do to reabsorption?
Released from atrial cells in response to stretching...directly inhibits Na reabsorption in the CD and suppresses secretion of renin
46
what is the effect of PTH on reabsorption?
Released in response to hypocalcemia and increase Ca reabsorption in thick ascending LoH and early DCT...decreases HPO4 reabsorption in PCT
47
In the PCT, the osmolarity of the filtrate (does/does not) change
does not; due to both water and solutes being reabsorbed
48
In the descending LOH, filtrate becomes (more/less/same) concentration because...
more because only water is reabsorbed
49
In the ascending LOH/early DCT, filtrate becomes (concentrated/dilute/remains neutral) since...
dilute since solutes are reabsorbed, but not water
50
In the late DCT and CD, filtrate becomes (more/less) diluted because... (trick question...but why?)
more diluted in the absence of ADH...less with ADH
51
What are the requirements for excreting concentrated urine?
ADH and hyperosmotic medullary interstitium
52
Substances that slow renal reabsorption of water cause what?
cause diuresis and therefore decreases blood volume
53
Caffeine does what to the kidneys?
inhibits Na reabsorption
54
Alcohol does what to the kidneys?
inhibits ADH secretion
55
pH= (classical formulation)
-log[H+]
56
pH= (Henderson-Hasselbalch Equation)
6.1 + log (HCO3-/.03 * PCO2)
57
Only multiply by .03 in the Henderson-Hasselbalch Equation if you (Did/Did Not) get the concentration of CO2?
Did Not
58
H+ secreted by PCT is essential to reabsorb what?
HCO3-
59
H+ secretion is driven by what?
Na reabsorption
60
As PCO2 levels rise in the blood and filtrate, there will be (less/more) H+ secretion leading to (more/less) HCO3- reabsorption?
more, more
61
What is the initial problem in Respiratory acidosis?
Increased PCO2 due to hypoventilation causes decreased pH
62
What compensation occurs during Respiratory acidosis?
Increased renal secretion of H+ and reabsorption of HCO3-...pH still slightly low even with compensation
63
what is the initial problem with Respiratory alkalosis?
Decreased PCO2 due to hyperventilation...increased pH
64
What is the compensation that occurs during respiratory alkalosis?
Decreased reabsorption of HCO3- and secretion of H+... pH will be slightly over 7.4
65
What is the initial problem during Metabolic alkalosis?
Increased free HCO3- (due to loss of acids or gain of HCO3-...increased pH
66
What is the compensation that occurs with Metabolic alkalosis
Hypoventilation causes increase PCO2 and pH will be slightly high
67
what is the initial problem with Metabolic acidosis?
Decreased pH, accompanied by decreased free HCO3- (due to gain of acids or loss of HCO3-
68
what is the compensation that occurs with Metabolic acidosis?
Hyperventilation which decreases PCO2 and the pH will be slightly low
69
What can the Anion gap tell you?
if metabolic acidosis is due to loss of HCO3- from the body or an accumulation of acids
70
Anion Gap=
Na- (Cl + HCO3-)
71
Normal Anion Gap values range from
8-16 mEq/L
72
If anion gap is normal, metabolic acidosis is due to what?
loss of HCO3- from the body
73
What can happen with an accumulation of H+ released from acids in metabolic acidosis due to accumulation of acids?
binds to HCO3- which decreases free HCO3- which decreases and the anion gap increases
74
Acidosis causes exchange of extracellular ___ for intracellular ____
H+ for K+
75
Alkalosis causes exchange of intracellular ___ for extracellular ____
H+ for K+
76
What is renal clearance?
volume of plasma from which a particular substance is completely removed per unit time (ml/min)
77
A substance can be cleared from the blood by the kidneys via what?
filtration and/or secretion (not reabsorbance)
78
To see if a substance has net reabsorption or secretion then compare it to what?
GFR of inulin/SCR and if it is higher then it is secreted
79
what is the formula for GFR?
(Uinulin*V)/Pinulin
80
What is the normal value of GFR?
125ml/min
81
what is the normal range of CrCL?
90-140 ml/min
82
which is more accurate and why (inulin vs. CrCl)
inulin...it is completely secreted from the body as the body has no physiologic need for/from it.
83
What is the formula for reabsorption?
filtered load - excretion rate
84
what is the formula for filtered load?
GFR*Ps
85
What is the formula for excretion rate?
Us * V
86
If a substance is bound to a protein such as albumin how will this affect its filtration?
decrease
87
What is the formula for secretion rate?
excretion rate - filtered load
88
What characterizes Acute renal failure?
A decrease in glomerular filtration rate
89
What is oliguria?
diminished urine output
90
What is anuria?
total cessation of urine output
91
What are pre-renal causes of acute renal failure?
result in decreased glomerular hydrostatic pressure and therefore decreased GFR. Comes from a decrease in intravascular volume or loss of effective blood volume
92
Renal failure due to kidney stones would be characterized as what?
Post-renal cause
93
Post-renal causes of renal failure decrease GFR by what mechanism?
increasing capsular hydrostatic pressure
94
Renal failure due to an ACE inhibitor would be characterized as what?
A pre-renal cause
95
Pre-renal causes of renal failure decrease GFR by what mechanism?
Decreasing glomerular hydrostatic pressure
96
What is the mechanism of an ACE inhibitor?
blocks vasoconstriction of efferent arteriole by ANGII which can lead to vasodilation and decreased GFR
97
What is the mechanism of an NSAID upon the kidleys?
block synthesis of prostaglandins and interfere with afferent arteriolar vasodilation causing a decrease in GFR
98
What is an Intrarenal cause of renal failure?
when direct damage occurs to the kidney rather than an obstruction or perfusion issue
99
What is a post-renal cause to renal failure?
obstruction of urine flow
100
Chronic renal failure will cause a ____ number of functioning nephrons and therefore a ____ GFR?
decreased, decreased
101
What can cause proteinuria?
damage to the glomerulus
102
What will prostaglandins do to the renal system?
mediated afferent arteriolar vasodilation in nephrons
103
what will ANG II do to the kidneys?
mediated efferent arteriolar vasoconstriction in nephrons
104
How can an ACE inhibitor delay the progression of chronic kidney failure?
by blocking ANGII which will cause vasodilation in efferent arterioles thus decrease glomerular hydrostatic pressure and preserves nephrons thru this mechanism.
105
Can chronic kidney disease be present with a normal or near normal GFR?
yes, if other markers are present
106
Serious symptoms usually do not occur in chronic renal failure until what?
loss of 70-75% of nephrons
107
what is the most common cause of death from renal failure?
cardiac dysfunction
