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中钙的含量，而将中钙的含量维持正常值范围内是由甲状旁腺素、降钙素与维生素D间的制约平衡所控制的。

And the master gland in your body is the pituitary, which produces many hormones that signal other glands — like the thyroid, parathyroid, adrenal, and pineal glands — to make their own hormones.

你体内的主要腺体是垂体，它产生许多荷尔蒙，向其他腺体发出信号——比如甲状腺、甲状旁腺、肾上腺和松果腺——制造自己的荷尔蒙。

Now, that calcium's still in the lumen, but parathyroid hormone also affects the distal convoluted tubule and increases calcium reabsorption.

这时，钙仍然腔内，但甲状旁腺素也会影响远曲小管，增加对钙的再吸收。

Related to this is pseudohyporparathyroidism, which is where the kidneys simply don't respond to parathyroid hormone because of a genetic defect in the parathyroid hormone receptor.

与此相关的是伪甲状旁腺功能减退症，也就是由甲状旁腺素受体的基因缺陷，肾脏不对甲状旁腺素作出反应。

Additionally, parathyroid hormone can boost 1-alpha-hydroxylase activity, which forms more active vitamin D, increasing gut absorption of calcium.

此外，甲状旁腺素可以增加1-α-羟化酶的活性，从而形成更多有活性的维生素D，增加肠道对钙的吸收。

So when the dust settles, as a result of parathyroid hormone, phosphate is lost in the urine while ionized calcium is kept in the blood, so ionized calcium levels rise and phosphate levels fall!

所以最终导致的结果是磷尿液中丢失，而游离钙被保存液中，因此游离钙含量上升，而磷含量下降！

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.

钙和磷不仅存骨中，也存液中，钙磷含量的调节受维生素D和甲状旁腺素（PTH）调控。

This affects the amount of parathyroid hormone that gets released by the parathyroid gland.

这从而会影响甲状旁腺释放甲状旁腺素的量。

Parathyroid hormone is produced by the parathyroid glands in response to low serum calcium, and it increases bone resorption to release calcium into the bloodstream.

顾名思义，甲状旁腺素甲状旁腺产生，来应对中过低的钙水平，从而增加骨质的吸收来释放更多的钙进入液。

If osteoporosis is really advanced, teriparatide, a recombinant parathyroid hormone can be used.

如果骨质疏松十分严重，可以使用特立帕肽这种重组甲状旁腺素治疗。

Less calcium entering the blood is the most common cause and can be due to hypoparathyroidism, or lower levels or lower activity of parathyroid hormone.

钙离子进入液的量减少是最常见的原因，可能是由甲状旁腺功能减退或者甲状旁腺素的量或者活性降低。

Ok, now let's have a quick look at parathyroid hormone.

好，来看甲状旁腺的功能。

The parathyroid hormone gets the bones to release calcium, and gets the kidneys to reabsorb more calcium so it's not lost in the urine as well as synthesize calcitriol also known as 1,25-dihydroxycholecalciferol also known as active vitamin D.

甲状旁腺素作用骨骼使其释放钙离子，也作用肾脏而增加钙的重吸收，这样钙就不会随尿液排出；以及用合成骨化三醇，也称为1，25-二羟基胆钙化固醇，又叫活性维生素D。

This can happen following a thyroid gland removal surgery when the parathyroids are accidentally taken out too or radiation treatment for cancer of the head or neck.

这可能发生甲状腺切除手术中，甲状旁腺可能被意外取出，或针对头颈部癌症进行的放疗过程中。

Lastly, parathyroid hormone increases calcium reabsorption and reduces the reabsorption of phosphate from the kidneys, so more phosphate is excreted through the urine.

最后，甲状旁腺素可以促进肾脏对钙的重吸收，而减少对磷的重吸收，因此导致尿磷升高。

Hormones are made by specialised cells mostly found in the endocrine glands, the hypothalamus, testes and ovaries, and the thyroid, parathyroid, pituitary, adrenal and pineal glands.

素由特化的细胞产生，这些细胞主要存内分泌腺、下丘脑、睾丸和卵巢，以及甲状腺、副甲状腺、垂体、肾上腺和松果体中。

We have teriparatide, which is a parathyroid hormone analogue that also reduces fracture risk and increases bone mineral density in patients with osteoporosis.

我们还有特立帕肽，这是一种甲状旁腺素类似物，能够降低骨质疏松症患者的骨折风险，并增加骨密度。

Now, even though parathyroid hormone stimulates bone resorption, it's been found that intermittent injections with teriparatide activates osteoblasts more than osteoclasts, therefore increasing bone formation.

其实，即使甲状旁腺素刺骨吸收，研究发现间歇性注射特立帕肽活了更多造骨细胞而非破骨细胞，从而增强骨生长。

The main endocrine glands are the pituitary, thyroid, parathyroid, adrenal, pancreas and gonads.

主要的内分泌腺为垂体、甲状腺、甲状旁腺、肾上腺、胰腺和性腺。

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

低钙症最常见的原因是甲状旁腺功能降低或甲状旁腺功能低下引起的PTH缺乏。