Renal blood flow and GFR Flashcards
Are renal nerves sympathetic or parasympathetic?
Sympathetic
Is the pressure in glomerular capillaries higher or lower due to the resistance downstream?
Higher - pressure doesn’t drop more than 2mmHg across length.
What are the Macula Densa cells involved with?
Negative feedback due to salt concentration at a given rate.
What are 2 properties of mesangial cells?
Phagocytic and Contractile
What makes up the 3 layers of the glomerulus?
Fenestrated endothelium, Basement membrance and Podocytes
What size of solute can be freely filtered?
What size will not be filtered?
> 70kDa
What is the GFR for a 70kg man?
125ml/min
In Glomerulonephritis does GFR increase or decrease?
Decrease: As the basement membrance becomes blocked or scarred.
In Glomerulonephritis what is now observed in the urine?
Protein and red blood cells
What are the two ways renal blood flow and GFR are regulated?
Myogenic and Tubularglomerular feedback
What happens when the afferent arteriole is constricted?
The rise in GFR is reduced and renal blood flow is reduced.
Which has the most effect: afferent or efferent constriction?
Afferent as there is a net decrease in GFR
What receptors in the macula densa cells detect salt delivery?
BS1/NKCC2 in brush border
Where do these cells signal too?
Mesangial cells to cause contraction of afferent arteriole or Granula cells involved in renin release..
