Dependence of rate constants of the glucocorticoid hormone-receptor interaction on steroid structure.

Making use of the methods developed earlier [P. Arányi and V. Quiroga, J. steroid Biochem. 13, 1167-1172 (1980)] rate constants of the steroid-glucocorticoid-receptor interactions were determined for a number of non-labeled analogues. Comparison of receptors from different species (chick thymus vs rat thymus) showed very similar specificities. Association rate constants varied over almost as large a range as did dissociation rate constants. Rate constants of the forward and reverse reactions are determined by the steroid structure apparently independently of each other.