TEMPERATURE AFFECTS O2-CARRYING CAPACITY OF CROSSLINKED HEMOGLOBINS

鉴于HBOCs在器官灌流中的潜在应用 在大手术期间停跳，或用于保存捐赠的器官 低温移植前，我们检查了温度依赖性。 几种化合物在15-37℃时的氧平衡曲线(OECs) 人和牛的交联型血红蛋白。这些血红蛋白的嗅鞘细胞 在装有恒温电池的Hemox分析仪上进行。OECs 对于37 oC的修饰血红蛋白，与 未修饰的血红蛋白。然而，降低温度会导致 增加了对氧气的亲和力。它将OEC转向了左翼。然而， 牛血红蛋白在β-β亚基上发生了交联 在极低的条件下，显著不同且更有利的氧合 温度。这就是新开发的改良人类的情况 血红蛋白与吡哆基四磷酸衍生物交联。这 这让我们相信，不仅是网站的修改，还有 化学修饰的性质在决定 负载时施加在血红蛋白上的构象约束程度 并卸载氧气。与它们结合的配体的动力学表征 血红蛋白目前正在使用快速反应技术，试图 血红蛋白功能的平衡和动态表现 在低温条件下。这项工作的一部分已发表在 BIOMAT。艺术。细胞免疫生物技术(1992)。一段简短的交流，描述 这部作品已经为出版做好了充分的准备。

In view of the potential application of HBOCs in perfusion of organs for cardioplegia during major surgery, or for preservation of donated organs at low temperatures before transplant, we examined temperature dependence profiles of oxygen equilibrium curves (OECs) at 15-37 Oc for a number of human and bovine cross-linked hemoglobins. OECs for these hemoglobins were carried out on the Hemox-Analyzer fitted with a thermostated cell. OECs for modified hemoglobins at 37 Oc were right shifted as compared to unmodified hemoglobin. Lowering the temperature however, resulted in increased affinity towards oxygen. It shifted OECs to the left. However, bovine hemoglobin cross-linked at the beta-beta subunits exhibited significantly different and more favorable oxygenation at very low temperature. Such is the case with a newly developed modified human hemoglobin cross-linked with a pyridoxyl tetraphosphate derivative. This led us to believe that not only the site of modification, but also the nature of the chemical modification plays a crucial role in determining the degree of conformational constrains placed upon the hemoglobin when loading and unloading oxygen. Kinetic characterization of ligand binding to these hemoglobins is now underway using fast reaction techniques in an attempt to relate both equilibrium and kinetic manifestations of hemoglobin function under hypothermic conditions. Part of this work has been published in Biomat. Art. Cell Immob Biotech (1992). A short communication describing this work fully has been prepared for publication.