RECENT DEVELOPMENTS IN MOLECULAR ACTION OF ANTIHORMONES

Antihormones are by definition antagonists of steroid hormone action. They interact with the ligand binding domains of steroid hormone recep tors and competitively inhibit the action of the receptors by mechanis ms that are not quite understood. In certain cases antihormones also e xhibit agonistic activity especially in connection with certain natura lly occurring receptor mutants. These observations together with findi ngs of indiscriminate interaction of antihormones with several classes of steroid receptors have necessitated a search of more effective and reliable antihormones. Recent advances in the resolution of the cryst al structure of the ligand binding domains of certain members of the s teroid receptor family and identification of non-liganded activation o f steroid receptors have produced considerable information that can be harnessed into a fruitful search for a new generation of antihormones .