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Old 07-15-2010
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Quote:
Originally Posted by Androide89 View Post
In physio kaplan it says renal venous o2 is the highest because it receives the highest blood flow/gram of tissue, but then goljan says the renal medulla has the lowest pO2, so low that it can induce sickling of RBC's in sickle cell trait even. Can someone explain. Thanks
ok i cant find exact explanation from books but im gonna try n give u an explanation of how i see it n if im wrong PLS correct me:

renal venous PO2 has to be high because the renal gets 25% blood flow. n medulla PO2 has to be lower if not blood from the renal medulla will flow into the renal veins so fast (blood flows from high to low pressures) causing blood to rush from the renal arteries into the veins so fast not allowing adequate GFR.

sigh... did that make sense? i guess what im tryin to say is that there must a low medulla pressure to ensure no renal blood "dumping" (there's no such renal blood dumping but if u can see what i mean here).
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