Risedronate Sodium (NE 58095 Sodium) is an aminobisphosphonate derivative of etidronic acid and CALCIUM CHANNEL BLOCKER that inhibits BONE RESORPTION and is used for the treatment of OSTEOPOROSIS.

Risedronate prevents the reduction of periosteal formation and the increase of endocortical bone resorption, thereby preserving the percentage of cortical bone and marrow area. It enhances osteoblast density and lacunar occupancy while preventing the augmentation of cortical bone porosity induced by GCs. Risedronate and Vitamin K(2) exhibit additive effects on bone density and lacunar occupancy and synergistic action against cortical bone porosity. At a dosage of 1 mg/kg in rats, Risedronate significantly increases the volumetric density of bone (Vb) and osteoblasts (Vob) and more notably reduces Vm. In rats, Risedronate dose-dependently and significantly decreases tooth movement following orthodontic force application.

At a concentration of 1 μM, Risedronate reduced the formation of colonies exhibiting osteoblastic characteristics, such as collagen accumulation, alkaline phosphatase expression, and mineralization. Conversely, 1 nM Risedronate and sodium alendronate increased the formation of fibroblast colonies, while not affecting the formation of colonies with osteoblastic traits. Risedronate completely inhibited the formation of fibroblastic colony-forming units in the calcification culture of rat bone marrow cells, whereas etidronate sodium had a comparatively lower effect. Additionally, Risedronate significantly suppressed the expression of c-Fos and nuclear factors in bone marrow-derived macrophages, specifically inhibiting the RANKL-induced activation of T cell clone c1.