Iodothyronine metabolism in liver and kidney homogenates from hyperthyroid and hypothyroid rats.
Iodothyronine metabolism in liver and kidney homogenates from hyperthyroid and hypothyroid rats.
复制标题
甲状腺功能亢进和甲状腺功能减退大鼠的肝和肾匀浆中的碘甲状腺原氨酸代谢。
作者：
Michael M. Kaplan;R. Utiger
研究了甲状腺功能亢进和甲状腺功能减退对大鼠肝脏和肾脏匀浆中T4向T3转化和rT3降解的影响。正常大鼠给予T4 （5 μg/100 g体重/天，连续5天），肝脏匀浆中两种反应的发生率均显著增加；10和20 μg/ 100g /d的T4剂量后，其增加幅度不明显。治疗12天后的疗效也不高于治疗5天后。甲状腺切除术后，T3产量在6周内逐渐下降至对照组的30%；rT3降解最初下降得更快，但在4周和6周时，两种反应的下降百分比相似。在t4处理的大鼠肾匀浆中，两种反应均未见明显变化。在去甲状腺大鼠的肾脏匀浆中，这两种反应在6周时都明显受损。这些结果扩展了先前的观察结果，即T4和rT3的5 ' -脱碘在不同的实验操作后呈平行方向变化，并且在不同的实验操作下，它们的去碘量呈平行变化。
The effect of hyperthyroidism and hypothyroidism on conversion of T4 to T3 and the degradation of rT3 was studied in rat liver and kidney homogenates. Administration of T4 (5 μg/100 g BW/day for 5 days) to normal rats resulted in significant increases in the rates of both reactions in liver homogenates; the increase was no greater after T4 doses of 10 and 20 μg/100 g/day. Responses also were no greater after 12 than after 5 days of T4 treatment. After thyroidectomy, T3 production declined gradually to 30% of control in 6 weeks; rT3 degradation initially decreased more rapidly, but at 4 and 6 weeks, the percentage of fall was similar for both reactions. No significant changes in either reaction were found in kidney homogenates from T4-treated rats. In kidney homogenates from thyroidectomized rats, both reactions were significantly impaired at 6 weeks. These results extend previous observations that 5′-deiodination of T4 and rT3 change in parallel directions after various experimental manipulations, and fur...