The effects of periosteum removal on the osteocytes in mouse calvaria

Abstract

Objectives: To investigate the early influence of periosteum removal on osteocytes in mouse calvaria. Material and methods: Fifteen C57BL/6 male mice were used in this study. Under anesthesia, a 2X3mm rectangular shape periosteum, 2mm behind the coronal suture and 1mm beside the sagittal suture, was surgically removed from the left side of calvaria whereas the right side was intact as control. Five mice were sacrificed at 1 day, 3 days and 7 days after the operation and the calvaria together with the surrounding tissues were histologically examined. Results: At 3 days and 7 days, the number of empty lacunae significantly increased at the periosteum stripped side compared to the intact control side. The empty lacunae were mainly restricted to the outer half of the calvaria under the periosteum stripped area. Sclerostin distribution in lacunae and canaliculi also dramatically decreased at the periosteum stripped side at all the time points. Conclusion: Periosteum removal would induce early apoptosis of the osteocytes in the outer layer of the bone and decrease sclerostin within this area.