Oxygen Binding of Modified Hemoglobins in Solution
The need for an oxygen-carrying blood substitute has been recognized for many years, and while various solutions and fluorocarbons have been tried, these have not met with the desired success. Though hemoglobin itself would seem a natural choice for this task, several undesirable properties must be overcome to render it suitable for large volume replacement applications. Hemoglobin, in concentrations appropriate for sufficient oxygen delivery to tissues, exhibits an undesirably high oncotic pressure, and is rapidly eliminated from the circulation. Additionally, in human red blood cells, the oxygen affinity of hemoglobin is partially regulated by 2,3-bisphosphoglycerate (BPG), (P50 = 24–30mm Hg), whereas hemoglobin, free in solution and devoid of BPG, has a much higher affinity for oxygen (P50 =12–16mm Hg) ; its ability to unload oxygen to tissues thus is substantially impaired.
KeywordsSodium Borohydride Hill Slope Oxygen Affinity Blood Substitute Hemoglobin Solution
Unable to display preview. Download preview PDF.
- 3.K. A. Evelyn and H. T. Malloy, Microdetermination of oxyhemoglobin, methemoglobin and sulfhemoglobin in a single sample of blood. J. Biol. Chem. 126:655–62 (1938).Google Scholar
- 5.L. J. J. Hronoski, Review of modified hemoglobin solutions for use as temporary blood substitutes. DCIEM No 85-R-51.Google Scholar
- 6.W. Lieberthal, E. F. Wolf, E. M. Merrill, N. G. Levinski and C. R. Valeri, Hemodynamic effects of different preparations of stroma free hemolysates in the isolated perfused rat kidney. Life Sciences 142(5):265–271 (1987).Google Scholar
- 8.L. R. Sehgal, S. A. Gould, A. I. Rosen, H. L. Sehgal and G. S. Moss, Polymerized pyridoxalated hemoglobin: a red cell substitute with normal oxygen capacity. Surgery 94(4):433–438 (1984).Google Scholar
- 9.T. Tanishima, Cerebral vasospasm: contractile activity of hemoglobin in isolated canine basilar arteries. J. Neurosurg. 53:787–93 (1980)Google Scholar
- 10.W. M. Vogel, R. C. Dennis, G. Cassidy, C. S. Apstein, and R. Valeri, Coronary constrictor effect of stroma-free hemoglobin solutions. Am. J. Physiol. (Heart Circ. Physiol. 20) H413–H420 (1986).Google Scholar