[Nonsteroidal antiinflammatory agents as modulators of glucocorticoid function of receptors]

The modulating effect of nonsteroidal antiinflammatory drugs (analgin, amidopyrine, sodium salicylate) on the function of types II and III glucocorticoidal receptors of cytosol in the Wistar rat liver was studied by Scatchard's and Laynuiver-Bark's analyses and dissociation rate constants for steroid-receptor complexes, by using natural and artificial glucocorticoids having a high specific activity. Analgin was not competitive in inhibiting the function of type II glucocorticoid receptors, decreased the association constant, increased the dissociation rate constant and reduced the elimination half-life of the labelled triamcinolone acetonide from the receptor. The density of type III glucocorticoidal receptors was many times increased with analgin. Amidopyrine had no noticeable effect on the function of type II glucocorticoidal receptors, however, repeatedly enhanced the density of type III glucocorticoidal receptors. Sodium salicylate was not competitive in suppressing the function of type II glucocorticoidal receptors and increased the number of sites of binding 3H-corticosterone to type III glucocorticoidal receptors. The latter fact can explain the mechanism of action of these drugs.