Differences in rat rbc cytosol induced after in vivo phenylhydrazine treatment

Analysis of rat red blood cell (RBC) cytosol protein fraction after in vivo phenylhydrazine treatment revealed increased amounts of 68-kDa protein. This protein is present in trace amounts in normal rat RBC cytosol. We also present data that 68-kDa protein from RBC cytosol has an identical isoelectric point, partial proteolytic map and immunological determinants as a protein of the same molecular mass from rat exosomes. These data indicate that 68-kDa protein is normally present in rat RBC cytosol, is exported via exosomes during reticulocyte maturation, and is increased in induced haemolytic anaemia.