Acetylsalicylic acid stimulates murine megakaryocyte precursor cells.

Depression of platelet function with a single intraperitoneal injection of acetylsalicylic acid was found to produce significant increases in several thrombocytopoietic indicators despite no observed change in platelet counts. There was an increase in the number of megakaryocytic precursor cells (small acetylcholinesterase positive or "SAChE+" cells), platelet size, and 35S incorporation into platelets. The results are qualitatively comparable to data from previous experiments showing that treatment of mice with a thrombocytopoiesis-stimulating factor (TSF or thrombopoietin) and rabbit anti-mouse platelet serum will elevate thrombocytopoiesis. The results presented herein indicate that interruption of platelet function by aspirin results in the production of new platelets, presumably by the action of a feedback system controlling thrombocytopoiesis.