Nakai K, Matsuda N, Amano M, Ohta T, Tokuyama S, Akama K, Kawakami Y, Tsuchida E, Sekiguchi S
Hokkaido Red Cross Blood Center, Sapporo, Japan.
Artif Cells Blood Substit Immobil Biotechnol. 1994;22(3):559-64. doi: 10.3109/10731199409117884.
The inhibitory effects of acellular and cellular hemoglobin (Hb) solutions on endothelium-dependent vasorelaxation were investigated in rabbit thoracic aortic strips. As acellular Hb solutions, 2,3-diphosphoglycerate (DPG)-depleted Hb and pyridoxylated Hb were examined. Cellular Hb solutions included washed human fresh red cells and liposome Hb encapsulated with pyridoxal-5'-phosphate (PLP). The tissues were precontracted with phenylephrine (PE), after which acetylcholine (ACh) was added to elicit a steady-state relaxation. Acellular Hb solutions cumulatively reversed ACh-induced relaxation, and these inhibitory effects reached a plateau at 10 micrograms/ml. Increasing oxygen affinity by pyridoxylation had little effect on this. In contrast, both red cells and liposome Hb solution showed moderate inhibitory effects, and they reached a plateau at 1 mg/ml. These findings indicate that acellular Hb solutions are more potent inhibitors than cellular Hb solutions by a factor of about 100, and that the encapsulation of Hb is a preferable method to mimic the red cell.
在兔胸主动脉条上研究了脱细胞血红蛋白（Hb）溶液和细胞血红蛋白（Hb）溶液对内皮依赖性血管舒张的抑制作用。作为脱细胞Hb溶液，研究了2,3-二磷酸甘油酸（DPG）耗尽的Hb和吡哆醛化Hb。细胞Hb溶液包括洗涤过的人新鲜红细胞和包裹有磷酸吡哆醛（PLP）的脂质体Hb。用去氧肾上腺素（PE）使组织预收缩，然后加入乙酰胆碱（ACh）以引起稳态舒张。脱细胞Hb溶液累积性地逆转了ACh诱导的舒张，并且这些抑制作用在10微克/毫升时达到平台期。通过吡哆醛化增加氧亲和力对此几乎没有影响。相比之下，红细胞和脂质体Hb溶液均显示出中等程度的抑制作用，并且它们在1毫克/毫升时达到平台期。这些发现表明，脱细胞Hb溶液作为抑制剂比细胞Hb溶液强约100倍，并且Hb的包裹是模拟红细胞的优选方法。
