Pharmacology

• Drugs


  Work by binding to specific protein molecules
• Protein molecules where drugs can bind

  • On the surface of a cell (receptor)
  • Specific enzyme molecules within a cell
• Drugs that act on receptors


  Can be classified as agonists or antagonists
• Agonist


  Mimics the natural compound and binds to the receptor molecules to produce a response similar to the natural active compound
• Antagonist


  Prevents the natural compound from binding to the receptor, and so blocks the natural response from occurring
• Drugs that act on enzymes

  Many are classified as enzyme inhibitors and act by binding to the active site of the enzyme and blocking the reaction normally catalysed there
• Drug shape and size

  • Interacts with a receptor binding site or to the active site of an enzyme
  • Interactions formed can include van der Waals forces and/or ionic bonds
  • Structural fragment of a drug molecule that allows it to form interactions with a receptor binding site or to an enzyme active site normally consists of different functional groups correctly orientated with respect to each other
• Identifying the structural fragment involved in drug action


  By comparing the structures of drugs that have similar effects on the body