Matsuzaki S, Suzuki M
Acta Endocrinol (Copenh). 1981 Aug;97(4):491-5. doi: 10.1530/acta.0.0970491.
The effect of sodium perchlorate (NaClO4) on the methylthiouracil-induced increase in the activity of thyroid glucose 6-phosphate dehydrogenase (G6PDH), ornithine decarboxylase (ODC) and polyamine contents was studied in the rat. The G6PDH activity was increased nearly three-fold by methylthiouracil (MTU) but not by ClO4- at 7 days of treatment. Perchlorate lowered the MTU-induced enzyme activity to nearly the control level, without changing circulating thyrotrophin (TSH). The anion had no inhibitory effect on G6PDH activity in vitro. The possibility that an inhibitor specific for G6PDH was generated in ClO4- - treated rat thyroids was excluded. The activity of ODC was greatly increased by both ClO4- and MTU, the increase being significant as early as on the second day of treatment. Perchlorate had no inhibitory effect on MTU-induced ODC activity in vivo but decreased total contents of spermidine and spermine in the thyroid, without affecting the concentration (nmoles/g wet weight) of the polyamines. These results suggest that ClO4- acts directly on the thyroid to suppress specifically the stimulatory effect of TSH on G6PDH activity and possibly on polyamine accumulation.
研究了高氯酸钠（NaClO4）对甲基硫氧嘧啶诱导的大鼠甲状腺葡萄糖6-磷酸脱氢酶（G6PDH）、鸟氨酸脱羧酶（ODC）活性增加及多胺含量的影响。在治疗7天时，甲基硫氧嘧啶（MTU）使G6PDH活性增加近三倍，但高氯酸盐未使其增加。高氯酸盐将MTU诱导的酶活性降低至接近对照水平，而循环促甲状腺激素（TSH）未改变。该阴离子在体外对G6PDH活性无抑制作用。排除了在高氯酸盐处理的大鼠甲状腺中产生G6PDH特异性抑制剂的可能性。高氯酸盐和MTU均使ODC活性大幅增加，早在治疗第二天增加就很显著。高氯酸盐在体内对MTU诱导的ODC活性无抑制作用，但降低了甲状腺中精胺和亚精胺的总含量，而不影响多胺的浓度（纳摩尔/克湿重）。这些结果表明，高氯酸盐直接作用于甲状腺，特异性抑制TSH对G6PDH活性的刺激作用，并可能抑制多胺积累。
