Standard aggregating media to test the "aggregability" of rat red blood cells

Rat red blood cells (RBC) exhibit low aggregation tendency in autologous pl asma and in standard aggregating media (e.g., 3% Dextran 70; MW: 70 kD). In experimental studies performed on rats, 3% Dextran 70 was found to be an u nsuitable suspending medium to test the "aggregability" of RBC in a standar d medium. It has been observed that solutions of higher molecular weight po lymers (i.e., dextran, MW: 500 kD; polyethylene glycole, MW: 35 kD; polyvin ylpyrrolidone, MW: 360 kD), at low concentrations were strong aggregators f or rat RBC. Among these polymer solutions 0.5% Dextran 500 and 0.75% polyvi nylpyrrolidone 360 were found to be the most suitable suspending media, to distinguish between the aggregability of RBC from septic and control rats. Therefore, these two polymer solutions are recommended as the standard aggr egating media for rat RBC, to test the RBC aggregability.