Cell proliferation in the bone marrow and thymus following fractures in rats.

Skeletal trauma in rats (tibial and femur fractures) stimulates bone marrow and thymus to increased mitotic activity during the first 2-3 days after the fracture. The stimulation is roughly of the same degree as that described in earlier investigations on the effects of calcium ion injections and moderate or major hemorrhages. The cause of increased mitotic level might be due to the release of kinins from the fracture area, factors which are known to stimulate mitoses of the bone marrow and thymus.