Bone remodelling as a whole is highly dependent on serum calcium levels, which, in turn, are kept in the normal range by a balance between parathyroid hormone, or PTH, calcitonin and vitamin D.

整个骨重建进程高度依赖于清中的含量，而将清中的含量维持在正常值范围内是由甲状旁腺激、与维生D间的制约所控制的。

As a result of low calcium, there may also be high PTH, which may also lead to low serum phosphate.

由于低，PTH可能会增高也会导致清磷酸盐低。

Now, the levels of calcium and phosphate in the bone, but also in the blood, are regulated by vitamin D and parathyroid hormone, or PTH.

和磷不仅存在于骨中，也存在于液中，磷含量的调节受维生D和甲状旁腺激（PTH）调控。

The most common cause of hypocalcemia is PTH deficiency, resulting from decreased function of the parathyroid glands or hypoparathyroidism.

低症最常见的原因是甲状旁腺功能低或甲状旁腺功能低下引起的PTH缺乏。

PTH acts to promote calcium release from bones and reduce calcium loss from urine.

PTH可促进从骨骼中释放，并减少尿中的流失。

PTH is produced in the parathyroid gland, while calcitriol is made in the kidney.

甲状旁腺产生甲状旁腺激，肾脏产生骨化三醇。

When serum calcium level is low, PTH is up regulated.

当清水较低时，PTH升高。