ISSN:
1432-1424
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Chemistry and Pharmacology
Notes:
Summary Among the amino acids which can be solubilized to give a concentration of 300 mM at near physiological pH, histidine and proline caused a complete hemolysis of newborn calf but not of adult cow red cells within 20 to 30 minutes at 38°C. While hydroxyproline, valine, and serine resulted in a partial lysis of calf cells, threonine, glutamine, and glycine were inefective. In this communication, emphasis has been focused on the mode of the lytic process by histidine, which was found to be affected by several governing parameters including the pH, temperature and the extracellular salts in the solution. Unlike human red cells suspended in isotonic histidine, both calf and cow cells lost little Na and K ions. In the presence of 300 mM histidine, both calf and cow cells displayed an instantaneous uptake of histidine amounting to 20 to 45 μmoles/ml RBC followed by a slow influx rate of 0.25 to 0.5 μmoles/ml RBC×min. The extent to which histidine entry was allowed by the cell was counterbalanced by Cl− efflux, resulting in little change in cell volume prior to hemolysis. Moreover, histidine-induced hemolysis can by prevented by 1 mM or lower PCMBS without at discernible effect on histidine influx suggesting a possible membrane lesion or damage at the outer surface of the cell. Hemolysis induced by histidine decreased substantially when a calf reached two months of age which time the red cells containing the fetal hemoglobin are virtually depleted. The results of hemoglobin electroiphoresis obtained during this postnatal period revealed that those cells resistant to histidine hemolysis almost invariably contain the adult type hemoglobin suggesting a selective, speicific action of the amin acid on the featal cells.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01868867
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