Matsuzaki S, Suzuki M
Endocrinol Jpn. 1975 Aug;22(4):339-45. doi: 10.1507/endocrj1954.22.339.
Thyrotropin (TSH) injected intraperitoneally caused a significant rise in the activity of L-ornithine decarboxylase of rat thyroid within 4 hr. TSH-releasing hormone (TRH) also increased the activity of this enzyme in a dose-related manner and of putrescine-activated S-adenosyl-L-methionine decarboxylase, probably through the increased secretion of TSH from the pituitary. Administration of methylthiouracil (MTU) in the drinking water to rats resulted in an increase of these two enzymes in the thyroid. Maximal activation was observed 4 days after the initiation of MTU treatment for both enzymes. The intracellular level of putrescine and spermidine increased during the rapid phase of thyroid enlargement caused by MTU treatment. The spermine concentration, however, was relatively constant during the treatment. The RNA/DNA ratio followed a pattern very similar to that exhibited by the spermidine/spermine ratio. These results indicate that TSH stimulates the biosynthesis of polyamines by increasing the activity of the decarboxylases in the thyroid. The findings further suggest that polyamines play a role in the regulation of thyroid growth and nucleic acid metabolism.
腹腔注射促甲状腺激素（TSH）可在4小时内使大鼠甲状腺中L-鸟氨酸脱羧酶的活性显著升高。促甲状腺激素释放激素（TRH）也以剂量相关的方式增加该酶的活性以及腐胺激活的S-腺苷-L-甲硫氨酸脱羧酶的活性，这可能是通过增加垂体分泌TSH实现的。给大鼠饮用含甲基硫氧嘧啶（MTU）的水会导致甲状腺中这两种酶的活性增加。在MTU治疗开始后4天观察到这两种酶的最大激活。在MTU治疗引起的甲状腺肿大的快速期，细胞内腐胺和亚精胺水平升高。然而，在治疗期间精胺浓度相对恒定。RNA/DNA比值的变化模式与亚精胺/精胺比值非常相似。这些结果表明，TSH通过增加甲状腺中脱羧酶的活性来刺激多胺的生物合成。这些发现进一步表明，多胺在甲状腺生长和核酸代谢的调节中起作用。
