Quantitative study of osteoclastic related factors in the process of bone reconstruction / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To detect the expression of osteoclast related factors, tumor necrosis factor-alpha (TNF-alpha), receptor activator of NF-kappaB ligand (RANKL) and tartrate-resistant acid phosphatase (TRAP), in the process of bone remodeling.</p><p><b>METHODS</b>8-week-old male C57BL/6J mice were employed in this study to detect the expression of osteoclast related factors by real time PCR.</p><p><b>RESULTS</b>TNF-alpha, RANKL and TRAP were up regulated in the process of bone remodeling, they reached the peak on day 2, 5 and 10 individually after injury.</p><p><b>CONCLUSION</b>Osteoclast related factors also participate in bone remodeling, which depends on the delicate balance between bone formation and bone resorption.</p>

Quantitative study of alkaline phosphatase and osteocalcin in the process of new bone / 华西口腔医学杂志

<p><b>OBJECTIVE</b>Alkaline phosphatase (ALP) and osteocalcin (OC) are the markers of new bone formation. Quantitative study of ALP and OC in the process of new bone formation helps to understand the ongoing of this cascade and contributes to make diagnosis in clinical treatment.</p><p><b>METHODS</b>8-week-old male C57BL/6J mice and primary osteoblasts from neonatal C57BL/6J mice calvaria were used in this experiment. HE staining, Northern blot and Real Time PCR methods were employed to detect the histological changes and the expression pattern of ALP and OC.</p><p><b>RESULTS</b>In vivo study showed that after fracture the expressions of both ALP and OC kept on increasing which were peaked on the 10 day, then started decreasing gradually. In vitro study on primary osteoblasts showed that the expressions of ALP and OC reached peak on the 14th day in differentiation culture medium and started decreasing from this time point till the 21st day.</p><p><b>CONCLUSION</b>The expression of ALP and OC in the process of new bone formation parallels with the development of osteoblasts, it increases with the differentiation of osteoblasts and becomes decreasing with the maturation of osteoblasts. The reciprocal relationship between the expression pattern of ALP and OC and development of osteoblast helps to maintain homeostasis.</p>