Bhattacharyya M, Chaudhuri U, Poddar R K
Department of Biophysics, Molecular Biology and Genetics, University of Calcutta, India.
Biochem Biophys Res Commun. 1990 Mar 30;167(3):1146-53. doi: 10.1016/0006-291x(90)90643-2.
Binding of chlorpromazine (CPZ) with human hemoglobin has been studied by equilibrium dialysis and fluorescence quenching. Results of equilibrium dialysis experiment when analysed by Hill plot revealed that the binding was positively cooperative with overall affinity constant K = 3.8 x 10(3) M-1. CPZ quenched the fluorescence of hemoglobin and the analysis of the quenching data by Stern-Volmer equation indicated two types of quenching process, namely, dynamic and static quenching. Dynamic quenching constant was measured from the decay of fluorescent life time of tryptophans of hemoglobin in presence of CPZ. Static quenching constant concerned with the ground state complex formation between CPZ and hemoglobin was found to be 5 x 10(3) M-1. Almost all the tryptophans of hemoglobin were found to be accessible for CPZ to interact with. Oxygen was found to be released when CPZ was added to hemoglobin. Extent of release of oxygen depends on the D/P ratio of CPZ(D): hemoglobin(P).
通过平衡透析和荧光猝灭法研究了氯丙嗪（CPZ）与人血红蛋白的结合情况。平衡透析实验结果经希尔图分析表明，这种结合具有正协同性，总亲和常数K = 3.8×10³ M⁻¹。CPZ猝灭了血红蛋白的荧光，用斯特恩 - 沃尔默方程对猝灭数据进行分析表明存在两种猝灭过程，即动态猝灭和静态猝灭。动态猝灭常数是通过在CPZ存在下血红蛋白色氨酸荧光寿命的衰减来测定的。发现与CPZ和血红蛋白之间基态复合物形成有关的静态猝灭常数为5×10³ M⁻¹。发现CPZ几乎可以与血红蛋白的所有色氨酸相互作用。当向血红蛋白中加入CPZ时发现有氧气释放。氧气释放的程度取决于CPZ（D）与血红蛋白（P）的D/P比值。
