Autoradiographic Studies of Cell Proliferation in the Periosteum of Intact and Fractured Femora of Mice Utilizing DNA Labeling with H3-Thymidine.

Abstract

An autoradiographic study of periosteal cell proliferation in intact and fractured mouse periosteum using 0.5[mu]c H3-thymidine/g of body weight showed that osteogenic cells are a relatively quiescent cell population awaiting a signal for proliferation and transformation as in fracture repair. Osteogenic cells constitute a self-sustaining cell population, which becomes diminished in size with increasing age. Osteoblasts are in part self-reproducing and in part produced by transformation of pre-osteoblasts. Fibroblasts of the fibrous layer of the periosteum do not appear to contribute cells to the osteogenic layer.