As for fixing human hearts? Perhaps manipulating thyroid hormone levels could be a start.

那类心脏能修复吗？也许可以从控制甲状腺激素水平开始。

If it's due to a primary cause, TSH will be low, an unbound thyroid hormones will be high.

如果是原发性甲亢，TSH水平将会很低，未结合甲状腺激素水平会变高。

Or like you start off by explaining it, okay, hypothyroidism, okay, it's obviously where you produce less thyroid hormone.

或者你开始解释，好，甲状腺功能减退，显然是你产生甲状腺激素较少。

Because when they added extra thyroid hormone to zebrafish's tanks, their tiny hearts were no longer able to regenerate.

因为当他们向斑鱼鱼缸中加入额外甲状腺激素时，斑鱼小心脏便不能再生了。

So, thyroid hormone for the win, right? What's not to love?

所以，甲状腺激素是最棒，对吗？还有啥理由不爱它呢。

Like steroids, thyroid hormone is lipid-soluble, so it crosses the membrane of its target cell to bind inside the nucleus.

像类固醇一样，甲状腺激素是脂溶性，所以它穿靶细胞膜与细胞核结合。

This results in growth of the thyroid glands and stimulates the follicular cells to produce excess thyroid hormone.

这会导致甲状腺增生并刺激滤泡细胞，产生甲状腺激素。

If there's too much thyroid hormone, they both decrease their own hormone production, to stop stimulating the thyroid.

如果甲状腺激素多，它们都会减少自身激素分泌，停止刺激甲状腺。

Another primary cause is toxic nodular goiter where one or more follicles starts generating lots of thyroid hormone.

另一个原发病因是毒性结节性甲状腺肿，即一个或多个滤泡开始产生大甲状腺激素。

Hassen called the lab. He ordered tests to check the level of thyroid hormone in the sample. It was very high.

哈森打电话给实验室，要求化验样本中甲状腺激素含。结果显示甲状腺激素含非常高。

Also anytime the thyroid gets inflamed or damaged there can be a large release of preformed thyroid hormones.

甲状腺发炎或受损，也可能大释放预先形成甲状腺激素。

That in turn reduces thyroid hormone levels in the blood, and slows down your metabolism again, before you get over-heated.

这反来会降低血液中甲状腺激素水平，并在你热之前再次减慢你新陈代谢。

A medication called methimazole, for example, decreases production of thyroid hormones.

例如，一种叫做甲巯咪唑药物会减少甲状腺激素产生。

And then if you need thyroid hormone to create DHT.

然后如果你需要甲状腺激素来生成DHT。

Too much thyroid hormone causes the body to race. Too little, and it slows to a crawl. Unchecked, either state can be fatal.

甲状腺激素多会导致身体处于亢奋状态。而甲状腺激素少，身体慢慢变得迟钝。如果放任不管，任何一种状态都可能致命。

Rarely, in some people - usually young, often male - too much thyroid hormone can make circulating potassium levels drop and cause weakness.

甲状腺激素会使循环钾含下降，继而导致虚弱，这通常出现在轻男性身上，但很罕见。

Perhaps manipulating thyroid hormone levels could be a start.

或许操纵甲状腺激素水平可能是一个开始。

And then also lowers thyroid hormone.

并且还会降低甲状腺激素。

So he might not have any issues with actual thyroid hormone synthesis.

所以他可能没有任何关于实际甲状腺激素合成问题。

All of them result in too much thyroid hormone in a hyper metabolic state where cellular reactions are happening faster than normal.

其后果都是产生多甲状腺激素，形成高代谢状态，即细胞反应比正常情况发生得更快。