Sypniewski E
Department of Pharmacy, Medical College of Virginia, Richmond 23298.
Ann Thorac Surg. 1993 Jul;56(1 Suppl):S2-6; discussion S6-8. doi: 10.1016/0003-4975(93)90548-v.
The thyroid hormones tetraiodothyronine and triiodothyronine (T3) are involved in a variety of biologic mechanisms. Thyroid hormones regulate protein, lipid, and carbohydrate anabolism and improve oxygen consumption in almost all body tissues. Thyroid hormone is formed by coupling of iodinated tyrosine molecules in the thyroid gland. Tetraiodothyronine is converted to T3, the active thyroid hormone. Drugs, disease states that induce severe physiologic stress, and surgical conditions (eg, cardiopulmonary bypass) can alter the levels of circulating active hormone by interfering with the peripheral conversion of tetraiodothyronine to T3. This low T3 ("euthyroid sick syndrome") state is manifested by low circulating levels of T3 and hemodynamic abnormalities. Active thyroid hormone replacement with T3, because of its pharmacologic actions, may be an ideal therapy in these conditions.
甲状腺激素四碘甲状腺原氨酸和三碘甲状腺原氨酸（T3）参与多种生物学机制。甲状腺激素调节蛋白质、脂质和碳水化合物的合成代谢，并提高几乎所有身体组织的氧消耗。甲状腺激素是由甲状腺中碘化酪氨酸分子偶联形成的。四碘甲状腺原氨酸转化为活性甲状腺激素T3。药物、引起严重生理应激的疾病状态以及外科手术情况（如体外循环）可通过干扰四碘甲状腺原氨酸向T3的外周转化来改变循环活性激素的水平。这种低T3（“甲状腺功能正常的病态综合征”）状态表现为循环T3水平降低和血流动力学异常。由于其药理作用，用T3进行活性甲状腺激素替代可能是这些情况下的理想治疗方法。
