Measurement of osmotic resistance of normal and pathological human red blood cells.

The changes in the osmotic resistance of red blood cells (RBC), due to various pathological conditions like exposure to heat, anemia as well as the effect of storage and anticoagulants have been investigated. The results have shown that exposure to a temperature of 50 degrees C makes the red blood cells fragile to osmotic pressures. Also, red blood cells from the patients suffering from anemia exhibited decreased osmotic resistance. Storage upto 9 days showed a marginal increase in the osmotic fragility of the RBC and beyond that, there was no significant effect upto 15 days. Also, exposure to anticoagulants like citrate, ammonium oxalate, and EDTA increased the osmotic fragility of the cells. The present study shows that the various traumas investigated will affect the mechanical properties of the red blood cell membrane.