RESUMEN
The role of arginine vasopressin ( AVP) played in proliferation and differentiation of mouse primary osteoblast and its mechanism was investigated. 100 nmol/ L AVP was added into the medium containing primary mouse osteoblast: (1) After being cultured for 72 h, the proliferation of the cells was counted with a cell counter. (2) The media of cultured cells on 2,4,6,8,10 days were harvested and tested for the secreted ALP concentration by osteoblasts, and the cells were lysed in order to test the ALP concentration in cytosol. (3) The alizarin red staining was employed to detect the effect of AVP on calcium nodules formation on 8 th and 20 th days. (4) The osteoblast cells were incubated with AVP for 20 min, and then were lysed. Radioimmune assay was applied to test the change of cAMP in cytosol. These results showed that, compared to negative group, 100 nmol/ L AVP significantly promoted the proliferation of primary mouse osteoblast ( P<0. 01). ALP secretion was increased remarkably ( P <0. 01), and the number and area of calcium nodules were increased considerably(P<0. 01). The intracellular cAMP was increased after incubating cells with AVP for 20min ( P<0. 01). These results suggest that AVP may promote proliferation and differentiation of mouse primary osteoblasts by cAMP signal pathway.