A comparison of thyroidal protection by stable iodine or perchlorate in the case of acute or prolonged radioiodine exposure
A comparison of thyroidal protection by stable iodine or perchlorate in the case of acute or prolonged radioiodine exposure
复制标题
DOI：
10.1007/s00204-020-02809-z
复制
发表时间：
2020-07-12
影响因子：
6.1
通讯作者：
Rump, Alexis
中科院分区：
文献类型：
--
作者：
Eder, Stefan;Hermann, Cornelius;Rump, Alexis
在核电站事故的情况下，可能会发生反复/长时间的放射性碘释放。放射性碘在甲状腺中积聚，通过辐射增加患癌风险。大剂量的非放射性碘可通过抑制放射性碘进入腺体（碘阻断）来保护甲状腺。这种保护作用基于细胞膜上活性载体位点的竞争以及沃尔夫 - 柴可夫效应，然而后者只是暂时的（24 - 48小时）。高氯酸盐可能仅通过载体竞争机制提供保护。然而，高氯酸盐对载体的亲和力比碘化物更强。基于一个为研究碘阻断而建立的生物动力学 - 剂量学模型，并在对其进行扩展以描述高氯酸盐的药代动力学以及通过载体的碘运输抑制之后，我们计算了在急性或长时间放射性碘暴露情况下，稳定碘或高氯酸盐能够实现的保护效力。在急性放射性碘暴露的情况下，考虑到其半数有效剂量（ED₅₀），高氯酸盐的效力不如稳定碘。100毫克稳定碘的剂量与1000毫克高氯酸盐大致具有相同的保护效力。对于长时间暴露，单剂量的保护剂，无论是稳定碘还是高氯酸盐，提供的保护都比急性放射性碘暴露后要低得多，因此似乎有必要重复给药。在长时间暴露的情况下，高氯酸盐对载体的较高亲和力以及碘的沃尔夫 - 柴可夫效应的减弱，使得高氯酸盐相比稳定碘具有更高的保护效力。考虑到不良反应的频率和严重性，在短期急性放射性碘暴露的情况下，等效剂量的碘和高氯酸盐似乎是可替代的，而鉴于在较长时间放射性碘暴露的情况下高氯酸盐具有更高的保护效力，应优先考虑高氯酸盐。
In the case of a nuclear power plant accident, repetitive/prolonged radioiodine release may occur. Radioiodine accumulates in the thyroid and by irradiation enhances the risk of cancer. Large doses of non-radioactive iodine may protect the thyroid by inhibiting radioiodine uptake into the gland (iodine blockade). Protection is based on a competition at the active carrier site in the cellular membrane and the Wolff-Chaikoff effect, the latter being, however, only transient (24-48 h). Perchlorate may alternatively provide protection by a carrier competition mechanism only. Perchlorate has, however, a stronger affinity to the carrier than iodide. Based on an established biokinetic-dosimetric model developed to study iodine blockade, and after its extension to describe perchlorate pharmacokinetics and the inhibition of iodine transport through the carrier, we computed the protective efficacies that can be achieved by stable iodine or perchlorate in the case of an acute or prolonged radioiodine exposure. In the case of acute radioiodine exposure, perchlorate is less potent than stable iodine considering its ED(50.)A dose of 100 mg stable iodine has roughly the same protective efficacy as 1000 mg perchlorate. For prolonged exposures, single doses of protective agents, whether stable iodine or perchlorate, offer substantially lower protection than after acute radioiodine exposure, and thus repetitive administrations seem necessary. In case of prolonged exposure, the higher affinity of perchlorate for the carrier in combination with the fading Wolff-Chaikoff effect of iodine confers perchlorate a higher protective efficacy compared to stable iodine. Taking into account the frequency and seriousness of adverse effects, iodine and perchlorate at equieffective dosages seem to be alternatives in case of short-term acute radioiodine exposure, whereas preference should be given to perchlorate in view of its higher protective efficacy in the case of longer lasting radioiodine exposures.