[Preventive effect of vitamin K1 and calcium on osteoporosis in ovariectomized rat]

Ovariectomized female Wistar rats[(170 +/- 15) g] were treated with vitamin K1 or/and calcium for 6 months, in order to study the effect of vitamin K or/and calcium supplementation on the prevention of osteoporosis. Vitamin K1(90 mg/kg) or/and calcium(5 g/kg) were added to a semisynthetic basal diet (VK 50 micrograms/kg, Ca5 g/kg). The findings of the study were as follows: Vitamin K1 treatment led to a significant increase of bone mineral density of the femoral diaphysis and lumbar spine, and bone ash content of the proximal one third of the femur shaft. The results suggested that vitamin K1 could, to some extent, prevent the fast bone loss and the femoral fragility induced by ovariectomy. Regarding the parameters of bone metrology and biomechanics, the effect of vitamin K1 combined with calcium on the prevention of osteoporosis is better than that of vitamin K1 or calcium alone, and the treatments with VK and Ca had better effects on femur than lumbar spine. The present study indicates that for postmenopausal women, as a risk population of osteoporosis, to increase their dietary intake of vitamin K and calcium might be helpful.