原发性甲状腺功能减退症的左甲状腺素治疗不会增加脑脊液中游离三碘甲状腺原氨酸的含量：一项初步研究。

L-thyroxine treatment in primary hypothyroidism does not increase the content of free triiodothyronine in cerebrospinal fluid: a pilot study.

机构信息

Department of Medicine, Karolinska Institutet, Karolinska University Hospital, Stockholm, Sweden.

出版信息

Scand J Clin Lab Invest. 2011 Feb;71(1):63-7. doi: 10.3109/00365513.2010.541931.

DOI:10.3109/00365513.2010.541931

Abstract

The association between cerebrospinal fluid (CSF) and serum concentration of thyroid hormones and pituitary thyrotropin stimulating hormone (TSH) was studied in nine hypothyroid patients (HT) before and in seven after L-thyroxine treatment. With L-thyroxine, median free T4 increased 4-fold in serum (3.5 pmol/L vs 17.5 pmol/L) and 3-fold in CSF, (3.9 pmol/L vs 11.5 pmol/L). Correspondingly, total T3 in serum increased two-fold (0.9 nmol/L vs 2.2 nmol/L). Unexpectedly, free T3 concentration in CSF was similar (1.5 pmol/L vs.1.5 pmol/L) before and during treatment. In HT, TSH in serum correlated with TSH in CSF as did free T4 in serum and in CSF. During L-thyroxine, the correlation with TSH in serum and CSF remained. Likewise, the free T4 concentration in serum correlated with that in CSF. However, no correlation was found between T3 in serum and free T3 in CSF. It seems evident that free T4 in serum equilibrates with that in the CSF both in the HT and during L-thyroxine. Despite a two-fold increase in total serum T3, free T3 in CSF remained unchanged, which agrees with previous results in rats showing that T3 is less exchangeable between serum and CSF. Alternatively, an accelerated conversion of T4 to T3 might have maintained the concentration of T3, due to strongly increased levels of TSH found in the hypothyroid state. The notion that free T4 in serum reflects the CSF concentration of free T4 is consistent with previous reports from studies in animals.

摘要

我们研究了 9 例甲状腺功能减退症（HT）患者在左甲状腺素治疗前后脑脊液（CSF）和血清中甲状腺激素及垂体促甲状腺激素（TSH）浓度的关系。用左甲状腺素治疗后，血清游离 T4 中位数增加了 4 倍（3.5 pmol/L 增至 17.5 pmol/L），CSF 中增加了 3 倍（3.9 pmol/L 增至 11.5 pmol/L）。相应地，血清总 T3 增加了 2 倍（0.9 nmol/L 增至 2.2 nmol/L）。出乎意料的是，CSF 中游离 T3 浓度在治疗前后相似（1.5 pmol/L 与 1.5 pmol/L）。在 HT 中，血清 TSH 与 CSF 中的 TSH 相关，血清游离 T4 与 CSF 中的游离 T4 相关。在给予左甲状腺素治疗后，血清和 CSF 中的 TSH 与 TSH 之间仍存在相关性。同样，血清游离 T4 浓度与 CSF 中的游离 T4 浓度相关。然而，血清 T3 与 CSF 中的游离 T3 之间没有相关性。显然，HT 患者和给予左甲状腺素治疗时，血清游离 T4 与 CSF 中的游离 T4 达到平衡。尽管总血清 T3 增加了两倍，但 CSF 中的游离 T3 保持不变，这与先前在大鼠中得到的结果一致，表明 T3 在血清和 CSF 之间的交换性较差。或者，由于甲状腺功能减退状态下 TSH 水平明显升高，T4 向 T3 的转化加速，可能维持了 T3 的浓度。血清游离 T4 反映 CSF 中游离 T4 浓度的观点与动物研究中的先前报告一致。