Originally Posted by bebix
Just think in numbers here:
If Q = RPF = 600 ml/min
FF = GRF / RPF
Normal FF = 20% ==> GFR 120 / RPF 600
Vc (AA or EA) will decrease Q = new Q 400 (doesn't matter really the number here)
Since AII Vc EA >>>AA = Hydrostatic pressure between both arterioles will also increase => GFR increases (because this number depends on the hydrostatic and oncotic pressure, and since HP goes up => more filtration)
net outcome => FF > 20%
Remember, FF is a percentage of RPF and not an absolute value...so even if the GFR stays the same, since the denominator decreases, the percentage must increase!
For more info, check here:
Concepts in medical physiology
Well said Bibex,
i actually tend to say that answer D and that was my answr before i read the kaplan text and videos of 2010
please watch the video in the link below and tell me if you can explain it
i really want to know what do you think?