Effect of the post-reserpine adrenergic block on thrombocytopoiesis and thrombocyte aggregation in rats

The effect of the post-reserpine adrenergic block (2 mg/kg for 3 and 6 days) on thrombocytopoiesis, bone marrow megakaryocytes (MKC) and thrombocyte aggregation was studied. A slight decrease in thrombocytes and a significant inhibition of 75selenomethionine incorporation in the newly-formed thrombocyte, more pronounced after 6-day reserpine treatment, was observed. The megakaryocytogram of the rats treated with reserpine for 3 and for 6 days manifested a similar significant decrease in MKC--as a total number and their separate stages. Thrombocyte aggregation was significantly inhibited, especially after the 6-day treatment. The inhibition of the megakaryocytopoiesis is probably the result of reduced metabolic processes, while thrombocyte aggregation probably results also from the serotonin depletion in the thrombocytes and the increased adrenaline level in the blood--phenomena observed after treatment with reserpine. It is concluded that the normal functions of the neuronal unit of the adrenergic transmitter system are necessary for the formation of an adequate number of functionally valuable thrombocytes.