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Old 03-27-2013
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Question P50 , affinity of Hb for O2

Hi guys, can someone explain me this statement...
A P50 change from 26mmHg to 20mmHg indicates the affinity for Hb is increased!

at 26mmHg 50% Hb is saturated and decreasing the PO2 to 20mmHg increases the affinity? its well understood graphically for me by looking at Hb-O2 dissociation curve.Can someone explain it in words for me to get better understanding of this concept.Thanks
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normally if you increase p02 ...HB will start to get oxidized and the point at which half the HB gets oxidized ...that point is p50 ...so if the point reaches early than before what would you say .....? the affinity of HB is increased and it takes less amount of O2 to fill half of it ....

i think you have misunderstood a bit ....pO2 is not decreased but p50 is decreased

hope it helps
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Originally Posted by npktun View Post
normally if you increase p02 ...HB will start to get oxidized and the point at which half the HB gets oxidized ...that point is p50 ...so if the point reaches early than before what would you say .....? the affinity of HB is increased and it takes less amount of O2 to fill half of it ....

i think you have misunderstood a bit ....pO2 is not decreased but p50 is decreased

hope it helps
I get it now, thanks.i framed the question wrong as i was confused.its clear now
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Originally Posted by docusmle9 View Post
I get it now, thanks.i framed the question wrong as i was confused.its clear now
glad i helped
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