摘要: Polycythemia in man is defined as an increase the hematocrit and hemoglobin concentration above accepted normal values. As such, finding of polycythemia implies increased production erythrocytes. Since red cell governed normally by interaction oxygen (O2) availability, elaboration regulatory hormone, erythropoietin, marrow function, it not surprising that derangements these interrelationships account for virtually all causes polycythemia. This chapter summarizes briefly various aspects regulation focuses on those identified mechanisms which lead to