Important Receptor Types to Know for Intro to Pharmacology

Receptors are essential for how drugs interact with the body. Understanding different receptor types, like GPCRs and ion channels, helps us grasp their roles in signaling and how medications can target these pathways for effective treatment.

1. G protein-coupled receptors (GPCRs)

   • Largest family of receptors involved in various physiological processes.
   • Activate intracellular signaling pathways through G proteins upon ligand binding.
   • Play a crucial role in drug development, with many medications targeting GPCRs.

2. Ion channel receptors

   • Allow ions to flow across cell membranes, altering membrane potential.
   • Critical for rapid signaling in neurons and muscle cells.
   • Can be gated by ligands (ligand-gated) or changes in voltage (voltage-gated).

3. Enzyme-linked receptors

   • Function as both receptors and enzymes, often involved in cell signaling.
   • Typically have an extracellular ligand-binding domain and an intracellular enzymatic activity.
   • Important in processes like cell growth, differentiation, and metabolism.

4. Nuclear receptors

   • Located within the cell nucleus and regulate gene expression upon ligand binding.
   • Bind to lipid-soluble hormones (e.g., steroids, thyroid hormones).
   • Play a key role in development, metabolism, and homeostasis.

5. Tyrosine kinase receptors

   • A subtype of enzyme-linked receptors that phosphorylate tyrosine residues on target proteins.
   • Involved in regulating cell division, survival, and metabolism.
   • Dysregulation can lead to cancer and other diseases.

6. Intracellular receptors

   • Bind to ligands that can cross the cell membrane, such as steroid hormones.
   • Regulate gene expression by acting as transcription factors.
   • Influence long-term cellular responses and adaptations.

7. Nicotinic acetylcholine receptors

   • A type of ion channel receptor that responds to the neurotransmitter acetylcholine.
   • Found in the neuromuscular junction and central nervous system.
   • Involved in muscle contraction and neurotransmission.

8. GABA receptors

   • Major inhibitory neurotransmitter receptors in the brain.
   • Mediate the effects of gamma-aminobutyric acid (GABA) to reduce neuronal excitability.
   • Targeted by anxiolytics and anticonvulsants in pharmacotherapy.

9. Adrenergic receptors

   • GPCRs that respond to catecholamines (epinephrine and norepinephrine).
   • Play a key role in the sympathetic nervous system and the "fight or flight" response.
   • Subtypes (α and β) mediate various physiological effects, including heart rate and blood pressure regulation.

10. Opioid receptors

    • GPCRs that bind endogenous opioids and exogenous opioid drugs (e.g., morphine).
    • Involved in pain modulation, reward, and addictive behaviors.
    • Targeted in pain management and treatment of opioid use disorders.