[Effect of steroid hormones on DNA matrix activity and glucocorticoid-receptor interaction]

The effect of 22 steroids on the matrix DNA activity was studied on thymocyte suspension of adrenalectomized Wistar male rats (80 to 100 g body weight) by means of 3H-uridine incorporation into acid-undissolved RNA fraction and 3H-triamcinolone acetonide-receptor interaction in thymocyte cytosol. Inhibiting effect of natural hormones on the labelled uridine incorporation into thymocyte RNA decreased as follows: dehydrocortisone greater than progesterone greater than pregnanediol greater than aldosterone greater than pregnenolone greater than 11-DOC greater than cortexolone greater than methyltestosterone greater than cortisone greater than 17 alpha-hydroxyprogesterone greater than androsterone greater than estradiol greater than aldactone greater than testosterone greater than pregnanetriol. All the steroids exerted an additive action on the glucocorticoid effect, with the exception of cortexolone, possessing antiglucocorticoid effect, and 11-DOC which did not influence dexamethasone glucocorticoid action. Almost all the steroids inhibiting 3H-uridine incorporation into RNA, competed actively with triamcinolone acetonide, concerning thymocyte cytosol binding with glucocorticoid receptor.