Effect of Rabbit Peripheral Sensory and Motor Nerve Homogenates on the Proliferation and Calcification of Rabbit Osteoblasts in Vitro

OBJECTIVE:To investigate the effect of rabbit saphenous and sciatic nerve homogenates on the proliferation and calcification of rabbit osteoblasts in vitro.METHOD:The saphenous nerves (sensory nerves) and the muscular branches of the sciatic nerve (motor nerve) were collected from 48 New Zealand white rabbits to prepare the nerve tissue homogenates. Bone marrow mesenchymal stem cells (MSCs) were isolated from the rabbits and cultured in vitro, and after 14 days of routine osteogenic induction, the resultant osteoblasts were identified by immunohistochemistry, alkaline phosphatase (ALP) and Alizarin red S staining. The osteoblasts were then incubated in the induction medium containing the saphenous (sensory nerve group) or sciatic homogenates (motor nerve group), with the cells in the dexamethasone-containing, dexamethasone-free osteogenic induction medium and control medium as the control. The proliferation, total protein and ALP activity of the osteoblasts were measured every other day until the 8th day, and Alizarin red S staining was used for quantitative analysis of calcification of the cells after two weeks.RESULTS:The application of the saphenous nerve homogenates significantly promoted cell proliferation, total protein and ALP activity (P<0.01, P<0.05 and P<0.05), while exposure of the osteoblasts to dexamethasone inhibited the cell proliferation (P<0.001). Compared to dexamethasone-free group, the saphenous homogenates enhanced the mineralization of the osteoblasts (P<0.001).CONCLUSION:Saphenous nerve homogenates significantly promotes the proliferation, differentiation, ALP activity and mineralization of rabbit osteoblasts, but sciatic nerve homogenates do not show osteogenic effects on the cells.