Laurberg P, Weeke J
Scand J Clin Lab Invest. 1977 Dec;37(8):735-9. doi: 10.3109/00365517709101858.
A sensitive radioimmunoassay for measurements of 3,3'-5'-triiodothyronine (reverse T3, rT3) in small amounts of unextracted serum is described. The interference of rT3 binding proteins in serum was precluded by addition of 8-anilino-1-naphthalene sulphonic acid (ANS). The cross reaction of T4 with the rT3 anti-serum varied with the concentration of T4 in the samples. At 50 per cent inhibition of [125I]rT3 binding, the T4 cross reaction was 0.075% (mol/mol). All values were corrected for T4 cross reaction. By the present method total rT3 averaged 0.37 nmol/l in thirty-two normal subjects. Higher values (0.81-1.98 nmol/l) were obtained in seventeen thyrotoxic patients, while the rT3 was very low (less than or equal to 0.046 nmol/l) in ten patients with severe primary hypothyroidism. A modification of the total rT3 assay was used for measurements of rT3 in serum dialysates (free rT3). The sensitivity was 0.46 pmol/l. This sensitivity did not allow detection of free rT3 in all normal subjects.
本文描述了一种用于测定少量未提取血清中3,3'-5'-三碘甲状腺原氨酸（反三碘甲状腺原氨酸，rT3）的灵敏放射免疫分析方法。通过添加8-苯胺基-1-萘磺酸（ANS）排除血清中rT3结合蛋白的干扰。T4与rT3抗血清的交叉反应随样品中T4浓度而变化。在[125I]rT3结合被50%抑制时，T4交叉反应为0.075%（摩尔/摩尔）。所有值均针对T4交叉反应进行了校正。用本方法测定，32名正常受试者的总rT3平均为0.37 nmol/l。17名甲状腺毒症患者的值较高（0.81 - 1.98 nmol/l），而10名严重原发性甲状腺功能减退患者的rT3非常低（小于或等于0.046 nmol/l）。总rT3分析方法的一种改良用于测定血清透析液中的rT3（游离rT3）。灵敏度为0.46 pmol/l。这种灵敏度无法在所有正常受试者中检测到游离rT3。
