Receptor Signaling Cascades

These flashcards cover key vocabulary terms and definitions related to receptor signaling cascades, important for understanding pharmacodynamics and signal transduction mechanisms.

Signal Transduction

The movement of signals within a cell, starting with ligand binding to receptors and leading to biological effects.

GPCRs (G-Protein Coupled Receptors)

The largest family of pharmacologically relevant receptors that mediate various physiological effects by activating G-proteins.

Agonist

A ligand that binds to and activates a receptor to produce a biological response.

Antagonist

A ligand that binds to a receptor but does not activate it, inhibiting the biological response.

Ligand-gated Ion Channels

Ion channels that open or close in response to the binding of a ligand, allowing ions to flow across the membrane.

Pharmacodynamics

What the drug does to the body, including receptor interactions and the resulting physiological effects.

Signal Amplification

The process where the activation of a receptor leads to a cascade of cellular events resulting in a larger biological effect.

Phosphorylation

The addition of a phosphate group to a molecule, often a protein, that can activate or deactivate its function.

Cytokine Receptors

Receptors that bind cytokines and are involved in cell signaling, particularly in immune responses.

Nuclear Receptor

Receptors that regulate gene transcription in response to lipophilic ligands like steroids and thyroid hormones.

Dose-Response Relationship

The relationship between the dose of a drug and its biological effect, often depicted by a curve on a graph.

Janus Kinase (JAK)

An effector kinase that is activated by cytokine receptors and phosphorylates the receptor to propagate signaling.

Tachyphylaxis

A rapid decrease in the response to a drug after repeated doses, often due to receptor desensitization.

Conformational Change

A structural change in a protein that often results from ligand binding and leads to receptor activation.

Ion Channel

A protein that forms a pore in a cell membrane to allow the passage of ions, critical for cellular signaling.