Qhov sib txawv tseem ceeb ntawm HbA thiab HbF yog HbA hais txog cov neeg laus hemoglobin uas yog α2β2 tetramer thaum HbF hais txog fetal hemoglobin, uas yog α2γ2 tetramer uas tuaj yeem khi rau oxygen nrog ntau dua affinity dua HbA.
Hemoglobin yog cov protein ntau hauv cov qe ntshav liab uas nqa cov pa oxygen ntawm lub ntsws mus rau cov ntaub so ntswg hauv lub cev thiab xa cov pa roj carbon dioxide los ntawm lub cev mus rau lub ntsws kom tshem tawm. Hlau yog ib qho tseem ceeb hauv kev tsim cov ntshav, thiab nws yog ib qho tseem ceeb ntawm hemoglobin. Muaj ob hom hemoglobin tseem ceeb xws li fetal hemoglobin (HbF) thiab cov neeg laus hemoglobin (HbA). Ntawm no, HbF yog thawj cov pa oxygen thauj cov protein hauv tib neeg fetus, thiab cov neeg laus hemoglobin hloov HbF kwv yees li rau lub hlis tom qab yug menyuam. Cov neeg laus hemoglobin yog hom tseem ceeb ntawm hemoglobin tam sim no hauv tib neeg. Ntawm HbF thiab HbA, HbF muaj kev sib raug zoo dua rau oxygen dua HbA. Raws li txoj cai, HbA yog α2β2 tetramer thaum HbF yog α2γ2 tetramer.
HbA yog dab tsi?
HbA sawv cev rau cov neeg laus hemoglobin, uas yog α2β2 tetramer. Nws yog cov hlau uas muaj cov qe ntshav liab cov protein ua lub luag haujlwm rau kev thauj mus los ntawm cov pa oxygen los ntawm lub ntsws mus rau cov ntaub so ntswg thiab lub cev, thiab kev thauj mus los ntawm cov pa roj carbon dioxide ntawm lub cev mus rau lub ntsws. Nws yog ib tug complex protein uas muaj plaub me me protein subunits thiab plaub pawg heme bearing hlau atoms. Hemoglobin muaj kev cuam tshuam rau oxygen. Muaj plaub qhov chaw sib txuas cov pa oxygen nyob hauv ib lub hemoglobin molecule. Thaum hemoglobin nkag mus nrog oxygen, cov ntshav yuav ua xim liab. Lub xeev thib ob ntawm hemoglobin hu ua deoxyhemoglobin vim nws tsis muaj oxygen. Hauv lub xeev no, cov ntshav yog xim liab.
Figure 01: HbA
Iron atom embedded nyob rau hauv lub heme compound ntawm hemoglobin tsuas yog pab txhawb cov pa oxygen thiab carbon dioxide kev thauj mus los. Kev khi ntawm oxygen molecules rau Fe+ 2 ions hloov pauv cov qauv ntawm hemoglobin molecule. Tsis tas li ntawd, hlau atoms nyob rau hauv hemoglobin pab tswj cov qauv ntawm cov ntshav liab. Yog li, hlau yog ib qho tseem ceeb hauv cov qe ntshav liab.
HbF yog dab tsi?
HbF sawv cev rau fetal hemoglobin uas yog hom tseem ceeb ntawm hemoglobin hauv fetus. HbF tsim los ntawm erythroid precursor hlwb. Qhov tseeb, HbF tshwm hauv cov ntshav hauv plab tom qab ob peb lub lis piam ntawm kev xeeb tub. HbF tseem nyob mus txog rau lub hlis tom qab yug menyuam thiab. Tom qab ntawd, cov neeg laus hemoglobin hloov HbF tag nrho. Zoo ib yam li HbA, HbF kuj yog tetramer. Tab sis nws muaj ob α-chains thiab ob gamma subunits.
Daim duab 02: HbF
Thaum piv rau HbA, HbF muaj kev sib raug zoo dua rau oxygen. Yog li, P50 ntawm HbF qis dua P50 ntawm HbA. Vim muaj kev sib raug zoo rau cov pa oxygen, cov pa oxygen dissociation nkhaus ntawm HbF yog sab laug-hloov piv rau HbA. Tsis tas li ntawd, qhov kev sib raug zoo siab dua ntawm HbF rau oxygen yog qhov tseem ceeb kom tau txais cov pa oxygen los ntawm leej niam txoj kev ncig.
Dab tsi yog qhov zoo sib xws ntawm HbA thiab HbF?
- HbA thiab HbF yog ob isoforms ntawm hemoglobin.
- Lawv yog cov proteins uas muaj hlau molecules.
- Thiab, lawv muaj affinity rau oxygen.
- Tsis tas li, ob leeg yog tetramers uas muaj plaub subunits.
- Dhau li ntawd, ob leeg muaj tib α-chains.
Qhov txawv ntawm HbA thiab HbF yog dab tsi?
HbA thiab HbF yog ob hom hemoglobin. HbA yog cov neeg laus hemoglobin, uas yog hom tseem ceeb ntawm hemoglobin hauv tib neeg, thaum HbF yog hom tseem ceeb ntawm hemoglobin hauv cov menyuam hauv plab. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm HbA thiab HbF. Raws li txoj cai, HbA muaj ob lub alpha chains thiab ob beta chains, thaum HbF muaj ob alpha chains thiab ob gamma chains. Yog li, qhov no kuj yog qhov sib txawv tseem ceeb ntawm HbA thiab HbF. Ntxiv mus, HbF qhia tau hais tias muaj kev sib raug zoo rau cov pa ntau dua li HbA.
Cov duab hauv qab no qhia txog qhov sib txawv ntawm HbA thiab HbF.
Summary – HbA vs HbF
Hemoglobin yog ib qho hlau-muaj metalloprotein pom hauv cov qe ntshav liab. Nws nqa cov pa oxygen los ntawm lub ntsws mus rau cov ntaub so ntswg ntawm lub cev thiab pab txhawb kev tsim hluav taws xob. Nws kuj tseem rov qab carbon dioxide los ntawm cov ntaub so ntswg lub cev mus rau lub ntsws kom tshem tawm ntawm lub cev. HbF yog daim ntawv tseem ceeb ntawm hemoglobin hauv kev tsim fetus thaum HbA yog hom tseem ceeb ntawm hemoglobin hauv tib neeg tom qab rau lub hlis tom qab yug menyuam. HbA yog tetramer tsim los ntawm ob alpha chains thiab ob beta chains thaum HbF yog ib tug tetramer muaj li ntawm ob alpha thiab ob gamma chains. Tsis tas li ntawd, HbF muaj affinity ntau dua rau oxygen dua HbA. Yog li, qhov no qhia txog qhov sib txawv ntawm HbA thiab HbF.
