Intro To RBF/GFR DSA Flashcards
Name some waste products that can be excreted by the kidneys
Urea Creatinine Acid Bilirubin Metabolites
How do kidneys respond to increase in water content
By increasing the output of water in the urine
What important blood pro-product do kidneys make
EPO
What is the stimulus for production of EPO
Decreased O2 in the Kidneys
The cortex of the kidney contains what
Corpuscles
Coiled blood vessels and coiled tubules
The medulla of the kidney contains what
Straight blood vessels and straight tubules
The kidneys receive aprox. How much CO
20%
The glomerular capillaries have what in terms of hydrostatic pressure
What about the peritubular capillaries
GC - high
PC - low
What is the purpose of the peritubular network
To reabsorb filtered fluid from the tubule lumen
What high hydrostatic pressure in the glomerular capillaries favors what
Filtration
Define vasa recta
Long medullary PTC
The rate and perfusion of renal blood flow in the kidney is highest and lowest where
Highest in the cortex
Lowest in the inner medulla
What do JG nephrons do
Secrete renin
What is the role of the PCT
Reabsorption of the largest fraction of glomerular filtrate
What is the role of the LoH
Urine concentration and secretion of Tamm-Horsfall Glycoprotein
What is the role of the DCT
Fine control of salt and water excretion
The podocytes are part of what in the glomerulus
The visceral part
What signals would cause vasoconstriction and lower GFR
NE
E
Endothelin
What signals would cause vasodilation and cause an increase in GFR
NO
Prostaglandin
ANP
DA
What does ANG II do to the GFR
Maintains it by selectively constricting efferent arterioles
Do systemic activation of the SNS due to baroreceptor reflexes (low P/BP) have much of an effect on RBF or GFR
No
ANG II effects which arteriole
Efferent
general SNS via a1 effects which arteriole most
Afferent
What produces the filtration slits
The podocytes
What are the layers in order that the filtrate must pass through to begin filtration
Endothelium
basement membrane
Podocyte filtration slits
What three things forms the glycocalyx
Proteins, hyaluronan, and heparan sulfate
What is the role of nephrin
Binds podocytes together and stope the passage of large proteins
What is the role of the Tamm-Horsfall Protein
Secreted by ThALoH
Inhibits Ca crystallization which stops kidney stones and UTI’s
What is the role of the glycocalyx
Produces a (-) charge which repels (-) proteins (anions) such as albumin
If there is a large amount of albumin in the blood, what can we surmise is wrong
An issue with the glycocalyx
What would happen in there was a large net loss of albumin
A decrease (Pi)GC which would mean less absorption and more filtration which would lead to edema
If excretion is greater than filtration, what has happened
Tubular secretion
Define renal clearance
The rate at which substances are removed from the plasma
Increased Cr means what in terms of GFR
Decreased GFR
What receptors activate increased Na/K ATPase and subsequently increased Na reabsorption to increase BP
A1
The a1 receptors act on which arteriole to cause vasoconstriction
Afferent
What does an increased BUN/Cr mean
A pre-renal problem
BUN REBS is increased (>20) which means hypovolemia, dehydration, decreased renal perfusion, or a high protein diet
What does a decreased BUN/Cr mean
An intrarenal problem
Ration <10 which means liver disease or a low protein diet
Increased PAH mean what
Increased RBF
