Red blood cell carbonic anhydrase I and zinc concentrations reflect a patient's integrate thyroid hormone level over the previous few months

本文测定了28例健康志愿者、46例甲亢、10例亚急性甲状腺炎、6例无症状甲状腺炎和4例促甲状腺激素分泌异常综合征（SITSH）患者红细胞碳酸酐酶I（CAI）和锌（Zn）含量。红细胞CAI浓度与红细胞锌浓度呈显著相关（r=0.95）。红细胞CAI和锌浓度下降，约90%的甲亢Graves病患者。抗甲状腺治疗后，这些物质的正常化滞后于血浆甲状腺激素水平约2个月。此外。在8周前测量的RBC CAI和Zn与血浆T4和T3水平之间观察到最高的相关性。亚急性甲状腺炎和无症状性甲状腺炎患者红细胞CAI和Zn浓度均正常，其中血浆T_4和T_3水平升高。临床甲状腺功能亢进的SITSH患者有低于正常值，但临床甲状腺功能正常的患者有正常值。结果提示：（1）甲亢患者红细胞CAI和Zn浓度反映了患者前几个月的平均甲状腺激素水平。（2）亚急性甲状腺炎和无症状甲状腺炎患者血浆甲状腺激素浓度升高是短暂的，对这些物质的影响很小。RBC CAI和Zn浓度的测量在临床上可能有以下用途：1）鉴别甲亢性Graves病与由于破坏性甲状腺炎引起的短暂性甲状腺功能亢进; 2）作为外周组织对甲状腺激素反应的标志物; 3）获得甲亢患者甲状腺激素水平随时间升高的程度的准确估计。

The red blood cell(RBC)carbonic anhydrase I(CAI)and zinc(Zn)concentrations were measured in 28 healthy volunteers, 46'patients with hyperthyroid Graves' disease, 10 patients with subacute thyroiditis, 6 patients with silent thyroiditis and 4 patients with syndrome of inappropriate thyrotropin secretion(SITSH). The concentration of RBC CAI was correlated to a significant extent(r=0.95)with the RBC Zn concentration. Both the RBC CAI and Zn concentrations were decreased in approximately 90% of the hypertyroid patients with Graves' disease. Following antithyroid therapy the normalization of these substances lagged behind that of plasma thyroid hormone levels by about 2 months. Furthermore. the highest correlation was observed between the RBC CAI and Zn and the plasma T4 and T3 levels measured 8 weeks earlier. Both the RBC CAI and Zn concentrations were normal in patients with subacute thyroiditis and silent thyroiditis in whom the plasma levels of T4 and T3 were elevated. The patients with SITSH who were clinically hyperthyroid had subnormal values, but clinically euthyroid patients had normal values. These results suggest that 1)both the RBC CAI and Zn concentrations in patients with hyperthyroidism reflect the patient's mean thyroid hormone level over the preceding several months. 2)in patients with subacute thyroiditis and silent thyroiditis, elevation of plasma thyroid hormone concentrations is transient and causes little change in these substances. And the measurement of RBC CAI and Zn concentrations may be useful clinically as follows : 1)in differentiating hyperthyroid Graves'disease from transient hyperthyroidism due to destructive thyroiditis ; 2)as a marker of the peripheral tissue response to thyroid hormone : and 3)in obtaining an accurate estimate of the extent of elevated thyroid hormone levels in hyperthyroid patients over time.