Summary
Intravenous injection of Phenylhydrazine into intact rabbits resulted in a thrombocytosis of 1.85 fold and megathrombocytosis (large platelets) of 2.30 fold. Splenectomy markedly impaired this response. The intravenous injection of red blood cell hemo-lysates gave a response similar to that of Phenylhydrazine in both intact and splenec-tomized animals. Basal data obtained from intact and splenectomized animals; as well as kinetic data obtained following apparent splenic blockade secondary to Phenylhydrazine hemolysis revealed the presence of a splenic platelet pool with preferential splenic sequestration of megathrombocytes.
It is suggested that the thrombocytosis and absolute megathrombocytosis of hemolysis is due to splenic blockade by red blood cell hemolysate.
