Fishman N, Huang Y P, Tergis D C, Rivlin R S
Endocrinology. 1977 Apr;100(4):1055. doi: 10.1210/endo-100-4-1055.
The effects of administration of 3,5,3'-triiodothyronine (T3) to normal and to hypothyroid male rats upon the hepatic activity of L-triiodothyronine aminotransferase were determined using 3,5-dinitro-L-tyrosine as substrate in the assay. Initial studies in normal rats demonstrated that basal enzyme activity was highest in liver and kidney of the organs tested, and that virtually no activity was detectable in skeletal muscle, serum, thyroid or pituitary gland. Hepatic enzyme activity increased from birth to a peak at 80-120 days and declined thereafter. Daily administration of T3 to normal rats in doses of 5 mug/100g BW for 8 days significantly elevated hepatic enzyme activity above normal. In daily doses of 2.5mug/100g BW, T3 restored the depressed enzyme activities in hypothyroid rats to normal. Daily administration of 3,3',5'-triiodothyronine (reverse T3) to normal rats in doses of 17.5 mug/100g BW and greater for 3 days increased L-T3 aminotransferase activity more than 30% above normal levels. Reverse T3 appeared to be approximately as active as T3 in increasing the hepatic activity of L-T3 aminotransferase.
在测定中，以3,5-二硝基-L-酪氨酸为底物，确定了向正常和甲状腺功能减退的雄性大鼠施用3,5,3'-三碘甲状腺原氨酸（T3）对肝脏L-三碘甲状腺原氨酸转氨酶活性的影响。对正常大鼠的初步研究表明，在所测试的器官中，肝脏和肾脏的基础酶活性最高，而在骨骼肌、血清、甲状腺或垂体中几乎检测不到活性。肝脏酶活性从出生到80-120天达到峰值，此后下降。以5微克/100克体重的剂量每日给正常大鼠施用T3，持续8天，可使肝脏酶活性显著高于正常水平。以2.5微克/100克体重的日剂量，T3可使甲状腺功能减退大鼠降低的酶活性恢复正常。以17.5微克/100克体重及更高剂量每日给正常大鼠施用3,3',5'-三碘甲状腺原氨酸（反T3），持续3天，可使L-T3转氨酶活性比正常水平提高30%以上。反T3在增加肝脏L-T3转氨酶活性方面似乎与T3活性大致相同。
