Caro J, Silver R, Erslev A J, Miller O P, Birgegard G
J Lab Clin Med. 1981 Dec;98(6):860-8.
The effect of T3 replacement and glucose supplementation on erythropoietin production was investigated in fasted hypoxic rats. It was found that 48 hr of fasting significantly reduced the circulating levels of thyroid hormones and the production of renal and extrarenal erythropoietin in response to hypoxia. These effects of fasting were completely abolished when the animals had free access to 25% glucose solution as drinking water, despite their lack of protein intake. Replacement doses of T3 (0.5 micrograms/100 gm per day) restored erythropoietin production in the fasted animals but also increased the response of the fed controls. To avoid the effect of endogenous T3, the experiments were repeated in thyroidectomized rats. Erythropoietin production in athyroid rats was found to be markedly decreased, with values equivalent to those found in normal fasted animals, and were not affected by fasting or glucose supplementation. Replacement doses of T3 increased erythropoietin production in all three groups, but the fasted animals needed five times as much T3 to obtain a response similar to that observed in the fed group. Glucose supplementation enhanced the effect of T3 in the fasted animals but did not completely restore it. These results indicate that caloric deprivation is primarily responsible for the decreased erythropoietin production induced by fasting and that this effect is probably mediated by both a decreased level of T3 and a decreased responsiveness to it.
在禁食的低氧大鼠中研究了T3替代和补充葡萄糖对促红细胞生成素产生的影响。发现禁食48小时可显著降低甲状腺激素的循环水平以及肾脏和肾外促红细胞生成素对低氧的反应性生成。当动物可以自由饮用25%葡萄糖溶液时，尽管它们缺乏蛋白质摄入，但禁食的这些影响被完全消除。T3替代剂量（每天0.5微克/100克）可恢复禁食动物的促红细胞生成素生成，但也增加了喂食对照动物的反应。为避免内源性T3的影响，在甲状腺切除的大鼠中重复进行了实验。发现甲状腺切除大鼠的促红细胞生成素生成明显减少，其值与正常禁食动物中的值相当，且不受禁食或补充葡萄糖的影响。T3替代剂量可增加所有三组的促红细胞生成素生成，但禁食动物需要五倍于T3的量才能获得与喂食组相似的反应。补充葡萄糖增强了T3对禁食动物的作用，但并未完全恢复。这些结果表明，热量剥夺是禁食诱导促红细胞生成素生成减少的主要原因，并且这种作用可能是由T3水平降低及其反应性降低共同介导的。
