Differential resistance to calcium-induced bilirubin-dependent hemolysis in mammalian erythrocytes.

Washed erythrocytes from human, buffalo, sheep and goat preincubated with different concentrations of calcium chloride (16.7-1830 microM) showed significantly different rates of hemolysis (up to 62%) after addition of bilirubin (72 microM). Goat erythrocytes displayed marked resistance to hemolysis with only 11% hemolysis observed at the highest calcium concentration. Similar trend in hemolysis was also observed when the concentration of CaCl2 was fixed (330 microM) and bilirubin concentration varied (0-72 microM). (Ca(2+)-Mg(2+)-ATPase levels were found significantly lower in goat and sheep erythrocyte membranes compared to human and buffalo erythrocyte membranes. This was correlated well with the observed hemolysis in various mammalian erythrocytes.