Influence of temperature variation from 5 degrees C to 37 degrees C on aggregation and deformability of erythrocytes.

Erythrocyte aggregation and elongation index (EI) (deformability) are measured at temperatures ranging from 5 degrees C to 37 degrees C by aggregometer MA1, and diffractometer Rheodyne SSD and the LORCA, respectively. The test samples are prepared from blood obtained from healthy subjects in test tubes containing EDTA as an anticoagulant and prior to measurement are placed in a water bath for 30 min, maintained at respective temperatures. The aggregation process is given in terms of primary aggregation time and indices of aggregation. These show significant to highly significant changes with the increase of temperature compared to that at 5 degrees C. The EI increases with the increase of shear stress but shows significant decrease with the decrease of temperature.