RBF/GFR (DSA + Lecture) Flashcards
What is the Tamm-Horsefall protein? Why is it seen in urine?
Protein produced by thick ascending loop of henle
Surpasses filtration of proteins in PCT, so ends up in urine
What two molecules are responsible for the negative charge of biogel? Where is biogel found?
Found over the fenestrations of capillary endothelium (in lumen)
Heparin Sulfates and Hyaluronin
What are three molecular fillers found in the filtration diaphragm?
Which one is specific to renal?
Cadherin, actin, and Nephrin
Nephrin is specific to renal
Role of molecular fillers?
Provide a physical barrier against larger molecules
What are 3 characteristics indicate a damaged filtration barrier?
Hypercellularity
Thickened Basement membrane (increases distance for filtration)
Glomerulosclerosis (increased extracellular tissue, so decreased SA for filtration)
Which part of the kidney has coiled blood vessels/ intertwined tubules?
Cortex
What 5 criteria is are necessary for a substance to be able to measure GFR?
- Can’t be broken down or metabolized by kidney
- Shouldn’t be reabsorbed or secreted
- Shouldn’t alter GFR
- Should have a stable plasma concentration
- Should be able to freely diffuse across the glomerulus
What happens to oncotic pressure of the efferent arteriole when GFR Increases?
It increases
What receptors lead to vasoconstriction of afferent arterioles?
Sympathetic stimulation of a1 receptors
What receptors lead to increased RAAS activation by the JGA cells?
Sympathetic stimulation of B1 receptors
What receptors lead to increased N/K ATPase functioning
Sympathetic stimulation of a1 receptors
(Results in more reabsorption of Na) –> more retention of water and increased blood volume
Immediate effects of sympathetic stimulation
- Vasoconstriction of afferent arterioles
- RAAS stimulation
- Decreased GFR
- Decreased RBF
- Increased Thirst
- Increased BP
Long term effects of sympathetic stimulation
- Decreased urine output
- Increased water intake
- Decreased Na secretion
What is a normal BUN:Creatine Ratio?
10:1
Post renal problem
What is a High BUN:Creatine Ratio?
20:1
Pre-renal problem