Receptor

Definition

Receptors are proteins on the surface of or within cells that bind to specific molecules, triggering a response in the cell. They play a crucial role in pharmacodynamics and homeostasis by mediating the effects of drugs and endogenous substances.

5 Must Know Facts For Your Next Test

1. Receptors can be located on cell membranes or within cells.
2. Binding of a drug to its receptor can either activate or inhibit cellular functions.
3. Receptor types include ion channel-linked receptors, G-protein coupled receptors (GPCRs), and enzyme-linked receptors.
4. The affinity of a drug for its receptor influences the drug's potency.
5. Desensitization or downregulation of receptors can occur with prolonged exposure to an agonist.

Review Questions

• What are the main types of receptors involved in pharmacodynamics?
• How does receptor binding influence drug effectiveness?
• What happens to receptor activity with prolonged exposure to an agonist?

Related terms

Agonist:

A substance that binds to a receptor and activates it, producing a biological response.

Antagonist:

A substance that binds to a receptor but does not activate it, blocking the action of agonists.

Affinity: The degree to which a drug binds to its receptor, influencing its potency.