Holm A C, Kågedal B
Department of Clinical Chemistry, Linköping University, Sweden.
J Clin Endocrinol Metab. 1989 Aug;69(2):364-8. doi: 10.1210/jcem-69-2-364.
We studied the initial uptake of L-T3 in erythrocytes isolated from normal subjects and patients with abnormal thyroid function. The uptake was saturable, with a mean maximum velocity (Vmax) of 3.60 pmol/min.10(8) cells and a Km of 248 nmol/L in normal subjects. Women had a somewhat lower Km but a similar Vmax compared to those in men. The Vmax was increased in patients with hyperthyroidism and decreased in those with hypothyroidism. Successful treatment lowered the initially high Vmax in hyperthyroid patients and raised the low Vmax in hypothyroid patients. One subject with the rare syndrome of thyroid hormone resistance had a Vmax in the upper normal range. The mean Km values of the hyperthyroid and hypothyroid groups and of the subject with thyroid hormone resistance were similar to that of the normal subjects. The results indicate that the initial saturable uptake of T3 by the human erythrocyte is increased in hyperthyroidism and decreased in hypothyroidism.
我们研究了从正常受试者和甲状腺功能异常患者分离出的红细胞对L-T3的初始摄取情况。这种摄取是可饱和的，正常受试者的平均最大速度（Vmax）为3.60 pmol/分钟·10⁸个细胞，米氏常数（Km）为248 nmol/L。与男性相比，女性的Km略低，但Vmax相似。甲状腺功能亢进患者的Vmax升高，甲状腺功能减退患者的Vmax降低。成功治疗使甲状腺功能亢进患者最初较高的Vmax降低，使甲状腺功能减退患者较低的Vmax升高。一名患有罕见的甲状腺激素抵抗综合征的受试者的Vmax处于正常范围上限。甲状腺功能亢进组、甲状腺功能减退组以及患有甲状腺激素抵抗的受试者的平均Km值与正常受试者相似。结果表明，人类红细胞对T3的初始可饱和摄取在甲状腺功能亢进时增加，在甲状腺功能减退时减少。
