Influence of the Thyroid Function on the Estrogen Metabolism

Abstract

Experimental studies were carried out for the purpose of investigating an influence of the thyroid function on estrogen metabolism. Firstly, the urinary estrogen of the patients with thyroid diseases was determined, and Ittrich's chemical estimation with a certain modification method was employed.
Then, Estradiol was administered to the women who had been castrated, and also to the amenorrhoic women ; all had been previously administered with the thyroid substance or antithyroid agent. They were observed for their urinary excretory pattern. The drug was composed of estradiol undecenoate 10 mg. with estradiol benzoate 2 mg., and was injected intramuscularly at the same time.
Investigation was made on the relation of estrogen to the thyroid function of the patients who had known thyroid diseases. The following conclusions were obtained.
1. Total estrogen in the thyroid patients revealed a value within the normal range. No difference between the cases of hyperthyroid and hypothyroid was found.
2. However, Et/Eo+Ed value had decreased in relation with increased function of the thyroid.
3. Estriol fraction was reduced when T₃ administered to the amenorrhoic patients. 4. No urinary estrogen variation was seen when the thyroid substance or antithyroid agent was administered to the castrated women.
5. When Estradiol was administered to the euthyroid women, the excretory estrogen reached a peak on the 4th day.
6. It was found that the estrogen metabolism would become accelerated when Estradiol was administered to the women treated with T₄ beforehand, but an increase of estriol was less when compared with those of either estrone or estradiol. Therefore, it might be concluded that conversion of estrone to estriol is hindered.
7. With the antithyroid drug, it was found that estrogen metabolism became much slower.
8. Influence of the thyroid hormone on estrogen metabolism was found to be identical whether in castration or in amenorrhea.
9. The drug effect was observed in the cases in which estrogen value was higher when T₃ treatment was tried in the women who had amenorrrhea or anovulatory cycle regardless of thyroid function before treatment.