THE EFFECT OF DIFFERENT STATE HEMOGLOBIN ON FUNCTION OF ERYTHROCYTE MEMBRANES
不同状态血红蛋白对红细胞膜功能的影响

It is well known that there are high and low affinity binding sites of Hb to erythroryte membrane. By means of fluorescent quenching of free Hb to both 12-AS labeled non-sealed and re-sealed ghost suspensions, we drew the conclusion that DeoxyHb mainly increased binding with high affinity site while MetHb mainly increased binding with the low affinity site, as compared to HbO2.Three parameters were used to characterize the effect of different types of Hb on membrane function (HbO2 as a control).(1) The rate of osmotic he-molysis. We found DeoxyHb decreased K2 (rate constant of the slow process) significantly while MetHb deereased both K1(rate constant of the fast process) and K2, which is in good agreement with the results obtained by fluorescent quenching. (2) Def or inability. We found both DeoxyHb aod MetHb increased Ci (the initial concentration of PEG for distinct formation of Rouleau), which means the less defor mability of erythrocyte. (3) Anion transport property. We found DeoxyHb decreased Ts (the permeability time of NO_2~(-)), which means that deoxygenation of erythroeyte can increase anion transport.Finally, the physiological importance of the effect of deoxygenation on me mbrane function was discussed.