Sensitivity of thyroid follicular cells to steroid hormones

Abstract

The results obtained during the studies on the effects of gonadal steroids on thyroid follicular cells (FC) of rats and pigs are summarized. The influence of a single (mg/animal) or double dose of estradiol-dipropionate (EDP) administered in different phases of male and female rat development was studied using cyto logical and stereological methods. A particular attention was paid to a characteristic inhibitory changes of thyroid FC of aged rats chronically treated with EDP and testosterone-propionate (TP). Chronic treatment of male rats, and the response of thyroid FC to hydrocortisone (Hy) was the object our investigations. Attention was focussed also on the specific changes in thyroid FC of newborn piglets treated with EDP and progesterone (Pr) in combination. The results revealed an inhibitory action of steroids on rat thyroid FC. In contrast, an increased activity of FC, after sex steroids treatment of piglets was observed.