Renal Module I Flashcards

1
Q

What space are the kidneys located?

A

Retroperitoneal

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2
Q

Which kidney is slightly lower?

A

right kidney (due to liver)

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3
Q

What are the kidneys protected by?

A

Posterior wall muscles and ribs

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4
Q

Approximately what are the measurements of the kidneys?

A

4-5 inches long, 2 inches tall

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5
Q

What arteries supply kidneys?

A

R/L renal arteries

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6
Q

How many liters of blood do the kidneys receive per minute? This accounts for how much of the cardiac input?

A

~1-1.25 L/min (20-25% cardiac output)

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7
Q

What is the dense connective tissue that surrounds the kidneys?

A

Renal capsule (fibrous capsule)

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8
Q

What is the layer of fat that provides shock absorption in the kidneys?

A

Renal fat pad

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9
Q

What is the connective tissue layer that surrounds the renal pad?

A

Renal fascia

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10
Q

What is a common symptom of many urinary tract diseases?

A

Flank pain/CVA tenderness

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11
Q

What causes flank pain?

A

Distention of the renal capsule, renal pelvis, and ureter

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12
Q

What causes “higher” flank patterns when compared to ureter pathology?

A

Kidney pathology

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13
Q

Severity of flank pain is directly related to what? What is it nor directly related to?

A

Directly related to speed of onset (but not degree of distention)

Ex. small kidney stone lodged in the ureter causes more pain than a slow growing, large tumor that distends the ureter

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14
Q

What is the outer region of the kidney that contains the nephrons?

A

Renal cortex

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15
Q

What is the inner region of the kidney that consists of renal columns and pyramids?

A

Renal medulla

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16
Q

What are the spaces located between each renal pyramid that contain nephrons?

A

Renal columns

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17
Q

What are the triangular shaped spaces that contain nephritic tubules (loop of Henle) and collecting ducts?

A

Renal pyramids

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18
Q

Where do the renal pyramids descend to?

A

The renal papilla (apex of the pyramids)

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19
Q

What is the urine pathway?

A

Flows from: Collecting ducts in the renal papilla (apex) -> minor calyce-> major calyce -> renal pelvis -> ureter
-> bladder

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20
Q

What do the calyces, renal pelvis, and ureters contain to facilitate the flow of urine into the bladder?

A

Smooth muscle

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21
Q

What is a ureteral stent (ureteric stent)?

A

Thin tube inserted into ureter to prevent or treat urine obstruction

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22
Q

Indications for a ureteral stent?

A

-Bilateral ureteral obstruction
-Obstruction of solitary functioning kidney
-Ureteric injury
-Post treatment of urolithiasis in pts w/ solitary kidney

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23
Q

When is pre-surgical ureteral stenting used?

A

Prophylactically in case of injury to ureter during surgery

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24
Q

What is considered the functional unit of the kidney?

A

Nephrons

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25
How many nephrons per kidney?
1.2 million
26
What is the role of nephrons?
Formation of urine
27
Structures of nephrons?
-Renal corpuscle -Glomerulus -Bowman's capsule/space -Proximal convoluted tubule -Loop of Henle -Distal convoluted tubule -Collecting duct
28
What are the two types of nephrons?
Cortical and juxtamedullary
29
What percentage of nephrons are cortical?
85%
30
Cortical nephrons extend partially into what structure?
Medulla
31
What are cortical nephrons responsible for?
Filtration, absorption, secretion, and excretion
32
What percentage of nephrons are juxtamedullary?
15%
33
Juxtamedullary nephrons extend deep into what structure?
Medulla
34
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
35
What are juxtamedullary nephrons responsible for?
*Urine concentration*, filtration, absorption, secretion, and excretion
36
"Capillaries from renal circulation that extend into Bowman's capsule/space" describes what structure?
Glomerulus
36
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
37
What is Bowman's capsule?
The first section of the nephron (entrance point)
38
The renal corpuscle is the site of what?
Filtration
39
Blood enters the glomerulus through what?
Afferent arteriole
40
Blood is filtered where?
Glomerulus
41
Plasma is filtered through what structure before entering Bowman's capsule? What is blood known as when it reaches Bowman's capsule?
Passes through glomerular filtration membrane, Blood is known as filtrate
42
What happens to blood that is not filtered by the renal corpuscle?
Exits glomerulus through efferent arteriole
43
What serves as the "filter for the nephron"?
Glomerular filtration membrane
44
What is the glomerular filtration membrane formed by?
Walls of both the glomerular capillary and Bowman's capsule
45
What are the three layers of the glomerular filtration membrane?
-Fenestrated endothelium of the capillary -Glomerular basement membrane (GBM) of the capillary -Podocytes formed by the epithelium of Bowman's capsule
46
What does the term mesangium (in the context of glomerular mesangial cells) refer to?
Space between the glomerular capillaries
47
Where are the glomerular mesangial cells located?
Centrally in space between glomerular capillaries
47
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
48
What do glomerular mesangial cells consist of?
Matrix of smooth muscle cells and phagocytic cells
49
Function of glomerular mesangial cells?
Contraction/relaxation to regulate filtration by altering surface area of glomerular filtration membrane & phagocytic removal of macromolecules
50
What is the proximal convoluted tubule (PCT) a continuation of?
Bowman's capsule
51
What is the PCT?
Single layer of simple cuboidal cells w/ microvilli that line the lumen wall
52
What do the microvilli of the PCT provide?
Large surface area for reabsorption/secretion (form a brush border similar to small intestine)
53
Function of the PCT?
Reabsorb most of the filtrate (60-95%) & secrete some drugs and meds (antibiotics, ACE-I, many other metabolic byproducts)
54
What is the loop of Henle formed by?
Descending limb and ascending limb-and its sub region known as the thick ascending limb (TAL)
55
Where is the juxtaglomerular apparatus (JGA) located?
Where the distal convoluted tubule passes by the glomerular arterioles
56
What is the role of the juxtaglomerular apparatus (JGA)?
Regulation of renal blood flow, glomerular filtration, and renin secretion
57
What kind of cells are in the juxtaglomerular apparatus (JGA)?
juxtaglomerular cells, mesangial cells, macula densa
58
What are juxtaglomerular cells in the JGA?
granular cells located adjacent to the afferent glomerular arteriole
59
What are mesangial cells in the JGA?
Continuation of mesangial cells from glomerulus
60
What are the macula densa of the JGA?
Specialized receptor cells located in the distal convoluted tubule that monitor sodium-chloride concentration of filtrate flowing through the nephron
61
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
61
What are the borders of the distal convoluted tubule?
Begin at macula densa, end at connection to collecting duct
62
What makes up the epithelium of the distal convoluted tubule?
Simple cuboidal cells w/ fewer microvilli than PCT cells
63
How is the distal convoluted tubule divided?
Functionally- into early DCT and late DCT
64
What is the function of the early DCT?
Continues to dilute filtrate, reabsorbs sodium
65
What is the function of the late DCT?
Begins to concentrate fluid as it enters the collecting duct
66
Numerous collecting ducts are found where?
In each renal pyramid
67
Each collecting duct will descend to the _____ and drain into the _____?
descend to renal papilla, drain into minor callyces
68
How many nephrons drain into each collecting duct?
Several
69
As the collecting ducts descend they merge to form about 30 ducts that open where?
Renal papilla
70
Epithelium of the collecting duct? What is the epithelium's important role?
Simple squamous epithelium line the collecting ducts Role: final fine tuning of urine concentration/water reabsorption, and urine dilution
71
Which filtration layer is a capillary wall with microscopic openings?
Fenestrated endothelium of the capillary
72
Openings in the fenestrated endothelium of the capillary are about how big?
60-80 nm
73
How large is a RBC?
8,000 nm
74
How large is a WBC?
8,000-15,000 nm
75
How large are most plasma proteins?
> or = 60 nm
76
The fenestrated endothelium layer of the capillary blocks what from passing?
Blood cells and some proteins (too large to fit through openings), but allows all other material to pass (small enough to fit through openings)
77
The fenestrated endothelium of the capillary has what charge? What lipoprotein lines the endothelium?
negative lipoprotein glycocalyx is negatively charged- small molecules that can fit through the openings may be repelled/prevented from passing (charge acts as a push back to acid in filtration)
78
Which filtration layer is a thin gel layer of collagen and other proteins (proteogycans, glycoproteins) that sits between the glomerular capillary wall and podocytes?
Glomerular basement membrane (GBM)
79
What are the three sub-layers of the GBM?
-inner/outer layers with negative charge -middle layer made of collagen matrix -spaces between collagen matrix creates ~10nm "pores"
79
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
80
How does the GBM potentially filter molecules?
Pore size (blocks molecules >7-10nm) Polarity (negative layer charge repels smaller molecules that are negatively charged)
81
Epithelium of bowman's capsule?
Podocytes w/ "foot-like" projections (that are negatively charged)
82
The foot like projections of podocytes wrap around what structure? What does this create?
Wrap around capillaries, creates matrix of ~40nm filtration slits/openings (also contain slit diaphragm/SD)
83
What is a slit diaphragm?
A layer formed by complex arrangement of micro-proteins (critical role in final ultrafiltration of plasma)
84
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
84
What is proteinuria?
Damage to the podocytes/slit diaphragms allowing for excess albumin & other plasma proteins to flow into the nephron
85
How do plasma proteins circulate?
In negatively charged lipoprotein packages
86
Plasma proteins?
Bilirubin, hemoglobin, albumin, immunoglobulins, fibrinogen
87
Can most plasma proteins and lipoprotein molecules pass through fenestrated openings (60-80nm) and the GBM (~10nm)?
No, most are too large to pass
88
Which plasma proteins are able to pass through openings/filtration?
Albumin (due to shape), and some other smaller proteins
89
Some albumin passes through the filtration membranes to the nephron while the rest is repelled by what?
Negative polarity
90
Why cant unconjugated bilirubin pass through the kidney if it is 1nm in size/able to fit?
Unconjugated bilirubin is not soluble in water, and cannot be renally excreted (needs to be bound to albumin to be soluble)
91
How do fats circulate?
Attached to protein carrier as negatively charged protein packages
92
Lipoprotein sizes?
HDL ~ 8-13 nm LDL ~ 18-23 nm VLDL ~ 30-80 nm chylomicrons ~ 75-1200 nm
93
Why are smaller lipoproteins repelled by the GBM & filtration slits?
negative charge
94
Pathology of what kidney structures will result in blood cells, proteins, or other substances to pass into urine?
-Glomerular capillary -GBM -Podocytes
95
Clinical meaning of proteinuria?
Excess level of proteins in urine, "foamy pee" (damage to podocytes lets excess albumin pass into nephron)
96
Clinical meaning of hematuria? What leads to hematuria?
Any condition where blood is found in the urine --> inflammatory pathology/damage to capillary wall or GBM will lead to hematuria
97
Are nephrotic and nephritic syndromes a specific pathology/disease?
No, generally represent lab findings associated with different renal pathologies/diseases
98
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
98
What does nephritic syndrome refer to?
Renal pathology that leads to hematuria as the primary finding *inflammation/damage to GBM/capillary wall
99
What does nephrotic syndrome refer to?
Renal pathology that leads to proteinuria (albumin) as the primary finding *damage to podocytes
100
Clinical findings with nephrotic syndrome?
-Proteinuria >3 g/d (protein/albumin in urine is diagnostic) -Hypoalbuminemia (low plasma albumin due to renal loss), edema as a result of altered albumin levels in the blood -Lipiduria: hyperlipidemia leads to lipids in the urine
101
Clinical findings with nephritic syndrome?
-Hematuria (microscopic or gross) -Red blood cell casts (tiny particles of RBCs found w/ microscope) -Proteinuria (mild to moderate: 1-3 g/d) -Oliguria: reduced urine production
102
What is minimal change disease (MCD)?
Damage to podocytes/foot projections by "effacement" or "fusion" that is difficult to see on light microscopy due to minimal changes *aka podocyte foot processes disease can be primary/idiopathic or have secondary causes
103
Minimal change disease (MCD) is associated with what?
Nephrotic syndrome
104
What is focal segmental glomerulosclerosis (FSGS)?
Segments of sclerosis in the glomeruli that can display alterations to the mesangial cells and/or loss ("effacement") of podocyte foot processes Can have primary or secondary causes
105
Segmental glomerulosclerosis (FSGS) is associated with what?
Nephrotic syndrome
106
What is Mesangiocapillary glomerulonephritis (MCGN) aka membranoproliferative GN (MPGN)?
Thickening of the mesangial matrix and glomerular capillary walls due to immune complex deposits and/or compliment factors ---> all leading to abnormal GBM formation
107
Mesangiocapillary glomerulonephritis (MCGN) is related to what?
Both nephrotic and nephritic syndrome
108
What is anti-GBM disease (Goodpasture's disease)?
Rare autoimmune disorder that affects kidneys and lungs --> attacks glomeruli capillaries (&alveolar capillaries), damaging GBM **Can be fatal if not treated
109
Anti-GBM (Goodpasture's disease) is associated with what?
Nephritic syndrome
110
Blood flows from the descending aorta to which structures of the kidneys?
R/L renal arteries
111
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
111
From the R/L renal arteries, multiple branches eventually bring the blood into what?
Afferent glomerular arterioles of the nephrons
112
Blood is filtered where in the nephrons?
Glomerular capillary beds
113
After being filtered in the glomerular capillary beds, blood flows out via what?
The efferent glomerular arteriole and enters the peritubular capillaries & vasa recta
114
From the peritubular capillaries and vasa recta, blood flows where?
Into venous return
115
What is the role of the afferent arteriole?
Regulates blood entering glomerular capillary bed: constriction or dilation alters filtration
116
What is the role of the efferent arteriole?
Regulates blood leaving glomerular capillary bed: constriction or dilation alters filtration
117
Renal circulation pressure of the glomerular capillaries?
Relatively high to encourage filtration, ideally ~ 55 mmHg *afferent&efferent arterioles regulate ideal glomerular capillary pressure
118
Renal circulation pressure of peritubular capillaries?
~8 mmHg to allow reabsorption & secretion along tubules of the nephron
119
Renal circulation pressure of vasa recta? What does vasa recta surround?
~8 mmHg to allow reabsorption & secretion -Surround loop of Henle in the juxtamedullary nephrons
120
Renal circulation pressure of venous return?
As blood leaves kidney: ~4 mmHg (typical of IVC pressures)
121
What is renal blood flow (RBF)?
Volume of blood that flows through the glomerular capillaries of both kidneys per minute
122
Average RBF?
1.0-1.2 L/min
123
At rest, what percentage of cardiac output flows into the kidney?
20-25%
124
What is renal plasma flow (RPF)?
Volume of plasma that flows through glomerular capillaries of both kidneys per minute
125
Average RPF?
600-700 mL/min
126
How to calculate RPF?
RPF = RBF (1- hematocrit)
127
What is glomerular filtration rate (GFR)?
Volume of plasma filtered into Bowman's capsule per minute
128
What determines GFR?
Net filtration pressure in the glomerulus
129
What is net filtration pressure (NFP)?
Net sum of 3 types of pressures acting between the glomerular capillary and Bowman's space
130
NFP of healthy adult?
~10 mmHg "pushing into" Bowman's capsule
131
Which three pressures form NFP?
-Hydrostatic pressure of glomerular capillary (~55 mmHg pushing into Bowman's capsule) -Hydrostatic pressure of glomerular capillary (~15 mmHg pushing into Bowman's capsule) -Osmotic pressure of glomerular blood (~30 mmHg pulling back into glomerular capillary)
132
What is filtration fraction (FF)?
% of renal plasma flow that filters into Bowman's capsule
133
Average FF?
20-25%
134
How to calculate filtration fraction (FF)?
GFR/renal plasma flow
135
Average GFR? What may cause average GFR to vary?
120 mL/min Varies w? age, sex, size
136
What is the gold standard test for measuring GFR? Is it ideal for clinical practice?
Insulin clearance, not ideal for clinical practice
137
What is insulin clearance testing?
Infusion of insulin and measure amount of insulin in urine
138
Why is insulin an ideal marker for GFR?
It is freely filtered by glomerulus and not secreted or reabsorbed in the tubules
139
Is creatinine easily filtered by the glomerulus?
Yes
140
How does the urine creatinine test overestimate actual GFR?
Creatinine is also secreted into the proximal tubule, which overestimates amount filtered by the glomerulus
141
What is a creatinine clearance (CrCl) test?
24 hour urine sample to measure amount of creatinine in urine, blood draw to measure amount of creatinine in the blood
142
How does CrCl estimate GFR?
Comparing amount of creatinine in urine w/ amount of creatinine in serum
143
Why is CrCl not routinely used in clinical practice?
Challenge of 24 hour collection
144
What is estimated cretinine clearance rate (eCCR) testing?
Blood draw to meaure amount of creatinine in blood
145
How does eCCR estimate GFR?
By calculating creatinine clearance using serum creatinine levels & other factors (age, sex, size)
146
What needs to be maintained in order to maintain GFR?
Net filtration pressure (NFP)
147
GFR is maintained by autoregulation if MAP is ______?
Between 80-180 mmHg
148
What GFR rate is used as an overall threshold for inadequate kidney function?
< 60 mL/min
149
MAP needed for autoregulation/maintenance of adequate GFR in a healthy individual?
"In theory" if MAP > or = 60 mmHg **Higher MAP values are used for clinical thresholds
150
What occurs when MAP drops too low to maintain NFP and GFR?
Acute renal insufficiency
151
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
151
What is the universal recommendation to avoid/minimize progression of acute renal insufficiency?
Maintain MAP > or = 65 mmHg
152
Evidence suggests that maintaining a MAP within 72-82 mmHg or more could be necessary to avoid acute renal insufficiency in patients with which conditions?
Acute septic shock and initial renal function impairment
153
What is chronic kidney disease (CKD)?
Abnormal kidney structure and/or dysfunction for >3 months that impacts health
154
Diagnostic criteria for CKD?
At least one of the following for at least 3 months: -GFR < 60 mL/min -objective measure of kidney damage/dysfunction: proteinuria, hematuria, abnormal electrolyte balance d/t renal cause, renal abnormalities detected by histology/imaging, kidney transplant
155
Stage 1 CKD values?
GFR >/= 90 mL/min, objective markers present
156
Stage 2 CKD values?
GFR = 60-90 mL/min, objective markers present
157
Stage 3 CKD values?
GFR = 30-59 mL/min, objective markers present or absent
158
Stage 4 CKD values?
GFR = 15-29 mL/min, objective markers present or absent
159
Stage 5 CKD values?
GFR = < 15 mL/min, objective markers present or absent
160
Ongoing evidence based guidelines are being developed to create other staging models for GFR that predict what?
Outcome risks
161
Intrinsic signaling of the kidney?
Renal autoregulation by two mechanisms: myogenic feedback and tubuloglomerular feedback *concerned with trying to maintain ideal GFR
162
Kidney is very effective at autoregulation if MAP remains between what values?
80-180 mmHg
163
Extrinsic signaling of the kidney?
SNS and RAAS signaling influence GFR *concerned with trying to maintain BP (influences GFR to maintain BP)
164
Autoregulation principles of glomerular arterioles?
-Afferent arteriole/blood entering glomerular capillary -Efferent arteriole/blood leaving glomerular capillary *will contract or dilate to alter filtration
165
What happens to filtration if the afferent arteriole constricts and/or the efferent arteriole dilates?
Filtration decreases
166
What happens to filtration if the afferent arteriole dilates and/or the efferent arteriole constricts?
Filtration increases
167
What is the myogenic feedback mechanism of intrinsic signaling?
Mechanical increase/decrease in pressure on arteriole wall SM stimulates contraction or relaxation reflex --> if systemic BP increases: myogenic feedback will relax or constrict afferent arteriole to adjust GFR and NFP
168
What happens during myogenic feedback if there is an increase in systemic BP?
Stimulates vasoconstriction of afferent arteriole (decreases excess GFR created by high systemic BP)
169
What happens during myogenic feedback if there is a decrease in systemic BP?
Stimulates vasodilation of afferent arteriole (increases low GFR created by low systemic BP)
170
What is the tubuloglomerular feedback mechanism of intrinsic signaling?
Macula dena monitors amount of NaCl flowing in the DCT --> if too much/too little NaCl flow, signals JGA to adjust GFR/restore optimal NaCl flow in the DCT
171
What happens during tubuloglomerular feedback if GFR is elevated?
Elevated GFR --> increases NaCl flowing through DCT Macula densa detects increased NaCl and signals juxtaglomerular (JG) cells to release ATP and adenosine --> ATP and adenosine stimulate mesangial cells of afferent arteriole to constrict, decreasing GFR (restoring optimal NaCl flow through DCT)
172
What happens during tubuloglomerular feedback if GFR is low?
Decreased GFR --> decreases NaCl flowing through DCT Macula densa detects decreased NaCl and signals juxtaglomerular (JG) cells to release nitric oxide and prostaglandins --> NO and prostaglandins stimulate mesangial cells of afferent arteriole to relax, increasing GFR (restoring optimal NaCl flow through DCT)
173
What effect do NSAIDS have on GFR/tubuloglomerular feedback?
Excess NSAID use can inhibit prostaglandin synthesis and signaling & may gradually decrease GFR **Chronic use can induce kidney injury
174
What is the role of SNS in extrinsic signaling of the kidneys?
Stimulates afferent arteriole vasoconstriction, decreasing GFR and NFP
175
During times of stress, exertion, or hypovolemic shock, the SNS will do what?
-Vasoconstrict most BV --> increases systemic BP -Directly decreases GFR by constriction of the afferent arteriole/rediraction of blood flow to other regions with increased need and/or to keep the body alive
176
What is the role of the RAAS (renin angiotensin aldosterone system) in extrinsic signaling of the kidneys?
Low systemic BP and SNS signal JGA cells in kidney to release renin --> renin converts angiotensinogen to angiotensin I --> ACE1 found in BV of lungs/glomerulus/other organs converts angiotensin I to angiotensin II *angiotensin II stimulates the adrenal gland to release aldosterone (stimulates nephron to retain sodium while ADH allows water to follow)
177
What is the effect of angiotensin II on GFR?
Vasoconstricts afferent and efferent glomerular arterioles *acts primarily on the efferent arteriole, has very small vasoconstrictive effect on afferent arteriole Net effect: vasoconstriction of efferent arteriole--> increases GFR
178
ACE-I/ARBs effect on RAAS/GFR?
Relax efferent arteriole --> decreases GFR ACE-I: block conversion of angio I --> agio II (less angio II) ARBs: block antio II R's (angio II can't constrict BV)
179
What structures make up the renal corpuscle?
Glomerulus, Bowman's capsule
179
Why are ACE-I and ARB effects a non-issue in kidneys with normal renal bloodflow?
ACE-I/ARBs may decrease GFR, but kidney is able to autoregulate/maintain GFR
180
Why are ACE-I and ARB effects a potential issue in kidneys with poor renal bloodflow (renal artery stenosis, etc.)?
ACE-I/ARBs may decrease GFR, and kidney may not be able to autoregulate/maintain GFR d/t poor renal bloodflow
181
Effect of natriuretic peptides (extrinsic signaling) on RAAS and GFR?
Counteracts RAAS, influence GFR
182
Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) are produced and secreted from what?
The heart and brain
183
How to ANP and BNP increase GFR?
Vasodilate glomerular afferent arteriole, stimulates diuresis and natriuresis Inhibit aldosterone, renin (RAAS) and sympathetic influence on kidney
184
What is renal natriuretic peptide secreted by and what is its role on the kidneys?
Urodilation- stimulates natriuresis and diuresis Secreted by: DCT/collecting ducts
185
What is C-type natriuretic peptide (CNP) produced/secreted by and what is its role on the kidneys?
Decreases systemic BP (vasodilates), may increase GFR Produced/secreted by: vascular endothelium
186
Renal artery stenosis (RAS) can cause what form of HTN?
Renovascular HTN
187
Renal artery stenosis (RAS) decreases bloodflow to the kidneys and causes what?
Decreased GFR, Decreased NaCl flow through DCT Dec. NaCl flow stimulates renin release-->stimulates RAS causing HTN
188
Why is renal artery stenosis (RAS) considered the silent killer?
Often does not cause signs/sx until RAS becomes severe
189
When should you suspect renal artery stenosis (RAS)?
Abnormal onset of HTN: HTN onset at young age, HTN worsens abruptly, kidney signs/sx, atherosclerosis in other arteries