farmacology

• • Pharmacodynamics = What the drug does to the body
  • Drug-receptor interactions
  • Dose-effect relationships
• • Exogenous compounds:
  • Natural products (Phytotherapy, Opium)
  • Synthetic drugs (aspirin, penicillin)
  • Physiological compounds:
  • Hormones (Testosterone)
  • Neurotransmitters (Acetylcholine)
• • Ligands can bind to receptors:
  • Antagonist = blocks the effect of a receptor 
  • Agonist:
  • Full agonist = results in full effect
  • Partial agonist = Smaller effect
• • Drug action components:
  • Drug
  • Receptor
  • Endogenous ligand
• • 3 factors for binding of a ligand (protein):
  • Shape
  • Size
  • Charge
• • Stereospecificity: 
  • Key-lock interaction, a receptor will only interact with a specific ligand
  • So another isomer of the same ligand will bind better or worse to the same receptor
• • Types of drug targets:
  • Human cellular targets
  • Proteins (receptors, enzymes, ion-channels, transporters and pumps)
  • Nucleic acids
  • For example: antibody therapy
  • Non-human targets
  • Microorganisms
  • Chemical targets (Ions, surfactants, bowel in GI-tract)
• Receptors:Ion-channeled coupled receptors   

  • G-protein coupled receptors
  • Enzyme-coupled receptors
  • Nuclear receptors
• Ligand-gated ion channels are very fast and many neurotransmitters use them, including GABA, Glutamate, and Serotonin.
• The effector mechanism of ligand-gated ion channels is ion-influx, which is the passage of ions through the channel.
• Some ion-channeled receptors have multiple sites of drug action.
• A main ligand and allosteric modulators are common in ligand-gated ion channels.
• Allosteric modulators influence the response to the main ligand in ligand-gated ion channels.
• G-coupled receptors are found in many neurotransmitters and neuropeptides.
• G-coupled receptors have many different types of effector mechanisms.
• The effector mechanism of G-coupled receptors is G-protein, which is a transmembrane domain.
• Noradrenaline and many other neurotransmitters use G-coupled receptors.
• Second messenger in G-coupled receptors is G-protein.
• Some G-coupled receptors stimulate, while others inhibit.
• Kinase receptor (enzyme coupled) receptors take longer than G-coupled receptors to activate and are often growth related, such as Insulin, growth factor, and cancer mutation.
• Nuclear receptors are the slowest of them all and their effector mechanism is RNA-synthesis.
• Receptors for nuclear receptors are often in cytoplasm.
• Steroid receptors are slow but powerful.