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Acellular and cellular hemoglobin solutions as vasoconstrictive factor.

K Nakai·N Matsuda·M Amano·T Ohta·S Tokuyama·K Akama·Y Kawakami·E Tsuchida·S Sekiguchi
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Abstract

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.

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2,3-DiphosphoglycerateAcetylcholineAnimalsAorta, ThoracicBlood SubstitutesDextransDiphosphoglyceric AcidsErythrocytesFemaleHemoglobinsIn Vitro TechniquesLiposomesMalePyridoxal PhosphateRabbitsSolutionsVasoconstrictionComparative StudyJournal ArticleResearch Support, Non-U.S. Gov't

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K Nakai, N Matsuda, M Amano, T Ohta, S Tokuyama, K Akama, Y Kawakami, E Tsuchida, S Sekiguchi. 1994. Acellular and cellular hemoglobin solutions as vasoconstrictive factor.. https://doi.org/10.3109/10731199409117884

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