Hemopoietic precursors: mechanisms of regulation under conditions of chronic stress.

We studied the content of hemopoietic precursor cells in the bone marrow, production of IL-1, IL-3, and colony-stimulating and erythropoietic activities by bone marrow cells under conditions of chronic stress. It was shown that in mice subjected to 15-h immobilization no hyperplasia of the bone marrow developed against the background of increased content of committed erythro- and granulomonocytopoietic precursors and enhanced production of short-distant humoral regulators of hemopoiesis, which reflects dysregulation of hemopoietic cells proliferation and differentiation processes in stressed animals.