Flashcards in Renal Blood Flow and Glomerular Filtrate I Deck (18):
What effect does constriction of the efferent arteriole have on GF?
Increases glomerular filtration
What is the best substance for measuring GFR and what is actually used clinically?
Inulin is the best
Creatinine is used
What does creatinine levels tell?
The glomerulus filtration rate (GFR)
How is inulin excretion related to its concentration in the plasma?
It is directly proportional
As plasma creatinine increases what occurs to excreted creatinine and why?
Decreases, it means GFR decreased thus the creatinine in the blood is not filtered out and increases (less excreted)
What affects selective permeability in the glomerulus?
Effective molecular radius
Why can proteins be found in the urine during a kidney infection?
The podocytes carry a negative charge, during an infection they may become damaged and lose their charge allowing negative proteins through
What is filtration fraction?
The volume of filtrate that forms from a given volume of plasma entering the glomerulus
What is the formula for FF?
Renal vessel vasoconstrictors:
Renal vessels vasodilators:
Atrial natriuretic peptide
What occurs to FF with increased afferent flow?
Decreases (doesn't have the ability to filter that much volume efficiently)
What occurs to GFR with constriction of afferent arteriole?
What is RPF?
Renal plasma flow: amount of plasma delivered to the kidneys per unit of time
What are the peritubular capillaries?
Follow the nephron tubules (branch from efferent)
Three parameters to calculate the clearance of solute X:
1.) Concentration of X in urine
2.) Volume of urine formed in a given time
3.) Concentration of X in systemic blood plasma
What is special about PAH (p-aminohippuric acid)?
It is completely removed in one pass through the kidney so it is a clinical test to measure renal plasma flow