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Updated: Jun 19, 2026

A Comprehensive Pipeline to Assess the Efficiency of Human Erythropoiesis In Vitro and Ex Vivo
Published on: January 10, 2025
FACTORS CONCERNED IN THE POLYCYTHEMIA PRODUCED BY THE SUBCUTANEOUS INJECTION OF EPINEPHRINE
1Department of Materia Medica and Therapeutics, University of Michigan Medical School, Ann Arbor.
The subcutaneous injection of epinephrine in doses of 1 mg. per kilo brings about a polycythemia, an increase in reticulocytes, and an increase in young forms of polymorphonuclear leucocytes. The polycythemia is no doubt in part a concentration phenomenon, but the presence of these young cells in increasing numbers is believed to be evidence that there is at the same time a discharge of cells from the blood-forming organs, due to the effect of the drug upon them. A similar effect is obtained by continued stimulation of the peripheral ends of the cut sciatic nerves in the curarized animal.
The subcutaneous injection of epinephrine in doses of 1 mg. per kilo brings about a polycythemia, an increase in reticulocytes, and an increase in young forms of polymorphonuclear leucocytes. The polycythemia is no doubt in part a concentration phenomenon, but the presence of these young cells in increasing numbers is believed to be evidence that there is at the same time a discharge of cells from the blood-forming organs, due to the effect of the drug upon them. A similar effect is obtained by continued stimulation of the peripheral ends of the cut sciatic nerves in the curarized animal.
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