[Changes in calcium regulating hormone in osteoporosis]

We summarized the changes of humoral factors, vitamin D, parathyroid hormone, and calcitonin in blood concentration, which are cooperatively regulating calcium homeostasis in aging and osteoporosis. Although these factors may play a important role on pathogenesis of osteoporosis in aged and postmenopausal osteoporotic patients, the influence of these factors on the mechanism of age-related or postmenopausal bone loss is unclear. There is no characteristic change of these factors in blood because of heterogeneity of osteoporosis and it is controversial. Further studies are required to evaluate the state of osteoporosis.