Do changes in bone marrow pressure contribute to the egress of cell from bone marrow?
Pressure was measured in the femoral medullary cavity of rabbits whose femoral muscles were subjected to electrostimulation. After electrostimulation the pressure in the medullary cavity increased fivefold. In groups of experimental animals the number of reticulocytes leaving the bone marrow and the number of reticulocytes in the peripheral blood were determined and it was observed that electrostimulation was followed by a severalfold rise in the amount of reticulocytes in both the bone marrow and the peripheral blood. The authors found that a great role in the egress of reticulocytes from the bone marrow into the circulation is played by regulation of the pressure in medullary cavity effected by changes in blood flow through the bone marrow.