前立腺腫瘍の実験的研究 IV: 実験的前立腺腫瘍発生に及ぼす甲状腺ホルモンの影響

Abstract

The role of endocrine environments on development of p rostatic tumors was studied on the thyroid hormone. As reported in the previous article, rats of Wistar strain were subjected to be injected 0.1cc of 20-MCT -Tween 80 solution into the prostate with simultaneous systemic administration of various thyroid agents. Occurrence of tumor was observed for about 6 months period. 1) The duratio ns by development of tumor were 90 days in the group given MMI as the fastest group and 110 days in the group given MUT. The duration was 130 days, however, in the group treated with thyroid powder or T3 which showed some delating effect on tumorgenesis. 2) The rates of incidene of tumors were 42.2 % with T3 and 46.9 % with thyroid powder in thyroid agent treated groups, and were 60.0 % with MMT and 57.8 % with MTU in anti-thyroid agent treated groups. This suggested us that administration of thyroid agents gives suppressive effect on development of tumor than that of anti-thyroid agents. 3) The weights of tumor were 0.935g in thyroid powder treated grou p, 1.178g in T3 group, 1.538g in MMI group and 1.903g in MTU group. Again here it was found that anti-thyroid agent treated groups showed 2 to 3 times higher proliferations than that of thyroid agent treated groups. 4) Histological exam ination of tumors revealed squamous cell carcinoma as the most frequent occurrence, being 60 to 80 % of tumors. Sarcoma and papilloma were the next frequent tumors. These results suggest us that abnormality of thyroid hormone has effects on development of experimental tumors of the prostate. Hyperthyroidal status due to administration of thyroid agents gives delayed and suppressive effects, while hypothyroidal status due to anti-thyroidal agents gives accelerative effects on development and proliferation of tumors. It will be concluded that development of prostatic tumor is participated not only in sexual hormonal environment but also in thyroid hormone through hypophyseal-adrenocortical system.