Fine structural alterations induced in erythocytes by phorbol myristate acetate.

Prevous studies have demonstrated that PMA is a potent membrane-active agent causing cell-wall derived vacuole formation in neutrophils and granule labilization in platelets. The present investigation demonstrates that PMA also has marked effects on red blood cells. Erythrocytes exposed to PMA were converted into stomatocytes and stomatospherocytes. The effects of PMA on red cells were concentration-dependent, required removal of plasma, and occurred maximally at 37 C. Although the response of the red cell to PMA was not identical to that of other blood cells tested previously; the similarities suggest that the capacity of the agent to produce membrane invagination may be fundamental to its mode of action.