Human progesterone receptor complexed with the antagonist RU 486 binds to hormone response elements in a structurally

D el-Ashry1, S A Oñate, S K Nordeen

  • 1Department of Pathology, University of Colorado Health Sciences Center, Denver 80262.

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Drug-Receptor Interaction: Agonist

Agonists are drugs that interact with specific receptors in the body to produce a biological response. When an agonist binds to a receptor, it activates or enhances the receptor's function, leading to physiological effects. The interaction between agonist drugs and receptors is crucial for their therapeutic action in various medical treatments.
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Drug-Receptor Interaction: Antagonist

An antagonist is a drug that binds strongly to a receptor without activating it. An antagonist prevents other molecules, such as neurotransmitters or hormones, from binding to the receptor and triggering a cellular response. Such interaction effectively hinders the normal physiological processes mediated by the receptor, resulting in various pharmacological effects depending on the specific receptor targeted.
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The Two-State Receptor Model

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Target Cell Response to Hormones

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