Evaluation of the effects of sensory denervation on osteoblasts by 3H-proline autoradiography

The inferior alveolar nerve was unilaterally resected in 30-day-old mice; other animals were unilaterally sham-operated. At 15, 30, 60, 90, or 150 days after surgery, the mice wee injected with 2 muCi of 3H-proline (sp. act. 1.0Ci/mM) per g of body weight and killed 15, 30, or 60 min later. Autoradiographs were prepared from 5 micron decalcified sagittal sections of mandibles and grain counts made over periosteal osteoblasts mesial to the first molar. In denervated mandibles, osteoblasts incorporated less isotope compared to controls with differences being maximal at the early intervals. These differences became attenuated with time, possibly due to an intrinsic compensatory mechanism, secondary to neurotrophic regulation.