RESUMO
BACKGROUND:Osteoblasts with high purity and activity are essential for bone metabolism research. OBJECTIVE:To explore a simple and effective culturing method of primary osteoblasts. METHODS:Osteoblasts were isolated from the parietal and frontal bones of newborn Sprague-Dawley rats using trypsin and collagenase digestion and tissue explant method. The morphology of osteoblasts was observed by inverted phase contrast microscope and transmission electron microscope;the cells was counted to draw the growth curve;the osteoblasts were identified by alkaline phosphatase BCIP/NBT staining and alizarin red staining. RESULTS AND CONCLUSION:The cells showed spindle, triangle or polygon shapes, having two or three protrusions. There were abundant mitochondria and endoplasmic reticulum under electron microscope, which presented the typical characteristics of osteoblasts. The cell growth was slow intially, accelerating at the 3rd day, and peaking at the 7th day. The cells were highly positive for alkaline phosphatase staining and were stained orangered through the alizarin red staining. To conclude, the cells isolated using enzymatic digestion combined with tissue explant method exhibit the typical characteristics and functions of osteoblasts, and this method is an ideal way to culture primary osteoblasts.