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Old 06-24-2012
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Default methemoglobin on the disassociation curve

Does met-hemoglobin cause a left shift in the Hb-oxygen disassociation curve?

I know carboxy-hemoglobin does, but i dont know if met-hemoglobin does.
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Old 06-25-2012
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MetHb---> More affinity for O2 ----> Dissociation curve shifted to left
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Old 06-25-2012
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methhemoglobin cannot bind to o2 bcz fe 2 plus is transformed to fe 3 plus so there are a decrease affinity to o2 the curve shift to the right
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Old 06-26-2012
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ok now im lost
is it left or right?
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Old 06-26-2012
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sryy for the left bcz it incrase the affinity of o2 to the remaning heme shif to the left and sureee
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Old 06-26-2012
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Met hb shifts the curve to the left.

Met hb exists in ferric form of hb (Fe3+)
thus it cannot bind any O2

it also prevents O2 release from the ferrous hb i.e Fe2+ form

thus curve shift to left .

still confused ? listen to dr goljan , he explains it pretty good.
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Old 08-21-2012
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Correct Answer

exactly like you guys said, metHb doesn't bind o2 as readily as Hb, so the blood will have a mixture of both of them, and the normal Hb will now have strong binding to o2. so the result is left shift of the curve.
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