The pH-resistance of erythrocytes: II. The influence of electrolytes

Abstract

The results of the investigations with citric acid-phosphate buffers in haemolysis suggest that a specific influence is exerted by the H+ ions, and thus by the pH of the external medium. This was checked with the aid of pure phosphate buffers, which gave exactly the same results (initial haemolyse: pH 5.1). In this way it could be proved that citrate exercised no anion-effect. A possible cation-exchange of Ca 2+, Mg 2+ and K+ ions for H+ ions in the erythrocyte membrane was investigated by following up the influence of these ions on haemolysis. In contrast to the haemolysis-depressing effect of small quantities of Ca 2+ ions in the osmotic haemolysis, no such influence could be detected in pH haemolysis, but a slight resistance-suppressing influence was detected. It was demonstrated that the Mg 2+ ions greatly suppress haemolysis with decreasing pH. Here too, the initial-haemolysis starts at a slightly higher pH. In the pro-lytic phase of the haemolysis a marked K +-shift from the cells occurs. The extra-cellular K+ concentration rises to very high values with decreasing pH.