[Effects of vitamin K on bone metabolism in tail-suspended rats]

Objective. To study the effects of vitamin K on bone metabolize in simulated weightlessness rats. Method. Male SD rats were divided into three groups (n = 9): the free active control (FAC), the tail-suspended control (SC), and the tail-suspended group treated with vitamin K (SVK) (50 mg/kg weight/d). The experiment lasted for 3 weeks. Bone biomechanical properties, bone mineral contents (BMC) and bone biochemical markers of bone metabolism were determined. Result. Compared with SC, total and bound bone gla protein (BGP) of serum, BMC of the femur and tibia, femoral mechanical properties, ALP activity of tibia all increased significantly; while NO content of femoral trunk decreased significantly. Conclusion. Vitamin K improved the bone metabolism and bone structure, decreased bone loss, increased bone biomechanical properties, decreased catagmatic fatalness. It proved that vitamin K prevented bone loss of simulated weightlessness rats.