甲状腺激素转运到细胞组织
新的研究表明通过细胞膜甲状腺激素转运在细胞内的碘甲状腺原氨酸（T3）的外围和垂体组织水平的重要作用，被证明有相当的临床意义。降低T4和T3转运到外周组织的细胞被认为是具有广泛的共同条件，包括胰岛素抵抗，糖尿病，抑郁症，双相性精神障碍，高脂血症，慢性疲劳综合症，纤维肌痛，神经变性疾病，偏头痛，紧张，焦虑，慢性节食和老化，而在垂体细胞内T3水平经常保持不受影响。
The pituitary has different transporters than every other tissue in the body. The thyroid transporters in the body are very energy dependent and are affected by numerous conditions, including low energy states, toxins and mitochondrial dysfunction, while the pituitary remains unaffected. Because the pituitary remains largely unaffected and is able to maintain intracellular T3 levels while the rest of the
body suffers from significantly reduced intracellular T3 levels, there is no elevation in thyroid-stimulating hormone (TSH) despite the presence of wide-spread tissue hypothyroidism, making the TSH and other standard blood tests a poor marker to determine the presence or absence of hypothyroidism. Because the T4 transporter is more energy dependent than the transporter for T3, it is also not surprising that T4 preparations are generally ineffective in the presence of such conditions, while T3 replacement is shown to be beneficial. Thus, if a patient with a normal TSH presents with signs or symptoms consistent with hypothyroidism, which may include low basal body temperature, fatigue, weight gain, depression, cold extremities, muscle aches, headaches, decreased libido, weakness, cold intolerance, water retention, slow reflex relaxation phase or PMS, a combination of both clinical and laboratory assessment, which may include a T3/reverse T3 ratio and the level of sex hormone binding globulin (SHBG), should be used to determine the likely overall thyroid status and if a therapeutic trail of straight T3 or a T4/T3 combination is indicated and not based solely on standard thyroid function tests.
©2014年，肯特·霍尔特夫，MD
杂志编辑©2014年，手臂
杂志康复医学2014;
DOI 10.14200 / jrm.2014.3.0104
