Renal part 1- Exam 3 Flashcards
Name the 7 functions of the kidneys
-Excretion of metabolic waste products and foreign chemicals
- Regulation of water and electrolyte balance
-Regulation of body fluid osmolality and electrolyte concentrations
- Regulation of arterial pressure
-Regulation of acid-base balance
-Regulation of Erythrocyte Production
-Secretion, metabolism, and excretions of hormones
In high altitudes the kidneys will produce ______, which causes what?
erythropoietin, which causes an in RBC which increases the oxygen carrying capacity
Are the kidneys (inside/outside) of the peritoneal cavity?
outside of the peritoneal cavity
What is the indented region of the kidney called?
hilum
What is the arrow pointing to?
the separating the cortex from the medulla
the kidney has _____ renal pyramids
8-10
Where are the nephrons located?
in the renal pyramids
How much blood is going into the kidneys in one minute?
1100 ml/min
The afferent arterioles leads where?
to the glomerulus
What are the two capillary beds of the kidney?
the glomerulus and peritubular capillaries
How does the kidney change the rate of filtration?
by changing the diameter of the afferent and efferent arterioles
What kind of capillary is associated with high hydrostatic pressure causes rapid fluid filtration
Glomerular capillaries
What kind of capillary is associated with low hydrostatic pressure permits rapid fluid reabsorption
Peritubular capillaries
Nephrons tends to decrease with ____
age
total glomerulus is encased in _____
Bowman’s Capsule
Fluid filtered from the ______ flows into ______ and then into the (proximal/distal) tubule which lies in the cortex of the kidney
glomerular capillaries
Bowman’s capsule
proximal
What things in the blood do NOT get filtered?
large proteins, RBC and albumin
What is the filtrate composed of?
plasma minus the proteins in your blood
Where is the majority of the work of that is being accomplished completed in the kidneys?
Proximal convoluted tubules
The loop of Henle: the ascending limb is (thick/thin)
both, has a thick and thin segment
The loop of Henle: the descending limb is (thick/thin)
thinner
The loop of Henle is found in the cortex or medulla?
Medulla
The cortex tubes are (thicker/thinner) than the tubes of the medulla?
thicker
At the end of the thick ascending limb is a short segment that has in its wall a plaque of specialized epithelial cell, known as the _____
macula densa
Where is renin being released?
at the macula densa
What are the two different types of nephrons?
cortical nephrons
juxtamedullary nephron
(Cortical/juxtamedullary) nephrons have nephrons that have glomeruli located in the outer cortex
Cortical
(Cortical/juxtamedullary) nephrons have Loops of Henle penetrate only a short distance into the medulla
Cortical nephrons
(Cortical/juxtamedullary) nephrons are 70% of the nephrons
Cortical nephrons
(Cortical/juxtamedullary) nephrons make up 30% of the nephrons
juxtamedullary
What is different about the juxtamedullary nephrons?
they have glomeruli that lie deep in the renal cortex near the medulla, they are very deep
_____ nephrons have long efferent arterioles extend from the glomeruli down into the outer medulla and divide into specialized peritubular capillaries called _____
Juxtamedullary
vasa recta
_____ nephrons play an essential role in the formation of a concentrated urine
Juxtamedullary
What does a GFR test for?
how quickly the filtrate is being formed
What is one substance that has no reabsorption
creatinine
What does a high serum creatinine indicate?
That the kidneys are not filtering as well as they should be
When looking at GFR ____ is quantitatively more important than _____
reabsorption
tubular secretion
______does play an important role in determining the amounts of K+ and H+ excreted in the urine
Secretion
what are the end products of metabolism that are poorly reabsorbed and end up in large amounts in the urine
urea, creatinine and uric acid
What 3 electrolytes are highly reabsorbed?
sodium, chloride and bicarb
____ and ____ are completely reabsorbed from the tubules and do not appear in the urine
glucose and amino acids
What does a high GFR indicate?
that the body is filtering the blood in the body very fast
How many liters of blood do the kidneys filter in a day?
180 Liters a day
How many liters of plasma do you have in your body?
3 liters
GFR = ____ of the Renal Plasma Flow
20%
What are the two main things that determine GFR
surface area for filtration and permeability/size of the substance
What is the capillary filtration coefficient?
What is
The product of the permeability and filtering surface area of the capillaries
The gomerular capillary membrane has __ layers
3
The glomerular capillary membrane all have strong _____ charges in the membrane hinder the passage of _____
negative
plasma proteins
The glomerular capillary membrane is more _______ but thicker
permeable
What does filtration depend on ?
size and electrical charge
____ will cause the surface area of the nephron to decrease
Diabetes
What three layers make up the filtration barrier?
Endothelium
Basement membrane
Epithelial cells
Layers of the glomerular capillary membrane: ______ Perforated by thousands of small holes (Fenestrations)
Endothelium
Layers of the glomerular capillary membrane _______: Negative charges to hinder the passage of plasma proteins
Endothelium
Layers of the glomerular capillary membrane _______: composed of a meshwork of collagen
basement membrane
Layers of the glomerular capillary membrane _______: Large spaces through which large amounts of water and small solutes can filter
Basement membrane
Layers of the glomerular capillary membrane _______: Line the outer surface of the glomerulus
Epithelial cells
Layers of the glomerular capillary membrane _______: not continuous continuous but have long foot-like processes that encircle the outer surface of the capillaries
Epithelial cells
What are long foot-like processes that encircle the outer surface of the capillaries?
(podocytes)
Epithelial cells are separated by gaps called _____
slit pores
Large substances cannot get through ____
nephrins
What does a filterability of 1 mean??
the substance is just as freely filtered as water
What 3 substances have the same filterability as water?
sodium
glucose
insulin
The pressure in the glomerulus might be (higher/lower) in order for it to go into the bowman’s capsule
Higher to force it into the Bowman’s capsule
Do we need to know these numbers?
dont know yet
What is the net filtration pressure?
10mmHg to force fluid out of the blood and into the bowman’s capsule
A kidney stone blocks the urethra and does not allow urine to flow, the urine backs up into the renal pelvis, collecting duct. What effect will this have on the Bowman’s capsule and GFR?
increases the pressure in the bowman’s capsule and decrease GFR
If the filtration coefficient increases, what happens to GFR?
GFR will increase
In what instances does the filtration co-efficent decrease?
in kidney disease due to destroyed glomeruli (chronic hypertension and diabetes)
Increasing Bowman’s capsule pressure (increases/decreases) GFR
decreases
A greater rate of blood flow into the glomerulus tends to (increase/decrease) GFR
increase
a lower rate of blood flow into the glomerulus tends to (increase/decreases) GFR
decreases
What is the Glomerular capillary hydrostatic pressure?
60mmHg
What are the three physiological regulations of GFR controlled by?
Arterial pressure
Afferent arteriolar resistance
Efferent arteriolar resistance
Increased arterial pressure (increases/decreases) glomerular hydrostatic pressure and (increases/decreases) GFR
Increases
increases
Increased resistance of afferent arterioles (increases/decreases) glomerular hydrostatic pressure and (increases/decreases) GFR
decreases
decreases
Constriction of efferent arterioles (Increases/decreases) the resistance to outflow – increases GFR
increases
Renal artery pressure is about equal to _______
systemic arterial pressure
The kidneys have an ______ system to maintain renal blood flow and GFR between _____ and ____
auto-regulation
80 and 170 mmHg
Under what condition would the SNS control the blood supply to the kidney?
under severe hemorrhage
under normal circumstances the kidney regulates itself
Very Strong Stimulation from SNS causes (dilation/constriction) of renal arterioles and (increase/decreases) flow and GFR
constriction
decrease
What 3 hormones constrict renal blood vessels and decrease GFR
Norepinephrine, Epinephrine and Endothelin
_____ is released by damaged vascular endothelial cells
Endothelin
Where is angiotensin II produced?
in the kidneys
Angiotensin II acts on (Afferent/Efferent) arterioles
Efferent
Afferent arterioles are protected from constriction by ____ and ______
nitric oxide and prostaglandins
What two effects does angiotensin II have on the efferent arteriole?
-raises glomerular hydrostatic pressure
-reduces renal blood flow
Decreased arterial pressure or volume depletion tends to (increase/decrease) GFR
decrease
Angiotensin II (increases/decreases) renal blood flow
decreases
Decreasing flow to peritubular capillaries causes a greater reabsorption of ___ and ____ and ____
Sodium
Potassium
Water
Memorize this chart
know this chart
What is Tubuloglomerular Feedback measuring? at what location?
Sodium chloride concentration NOT PRESSURE with the control of renal arteriolar resistance
macula densa
What kind of cells are located on the outside of the afferent and efferent arteriole?
juxtaglomerular cells
Where are the macula densa cells?
group of epithelial cells in the distal tubules of the macula densa
If GFR decreases, filtrate has (more/less) time to be reabsorbed
more time
What does a decrease in macula densa sodium chloride concentration cause?
dilation of the Afferent arterioles and increased in renin release
Be able to draw this flow chart
be able to draw this chart
What are the two effects of the macula densa in response to low sodium
- Decreases resistance to blood flow in the afferent arterioles
- Increase renin release from the juxtaglomerular cells of the afferent and efferent arterioles
When renin is released, what happens?
Functions as an enzyme to increase the formation of angiotensin I which is converted to angiotensin II
____ provides auto-regulation in the kidney
juxtaglomerular complex
T/F: The GFR changes drastically with large fluctuations in arterial pressure
False: GFR only changes a few percentage points, even with large fluctuations in arterial pressures between 75 – 160 mm Hg
What is the MOA of ACE inhibitors? What does this cause?
Preventing angiotensin II formation causes reductions in GFR
What are 3 complications of ACE inhibitors
Renal artery stenosis
Decreases GFR
Sudden Renal failure
