Pharmacology

• Drug


  a chemical substance of a known structure, other than a nutrient or an essential dietary ingredient, which, when administered to a living organism, produces a biological effect
• Drugs alter the activity of biological processes to

  • prevent disease - prophylaxis
  • restore normal function of biological process that has become deregulated
  • alter the activity of a compensatory pathway
  • in infection - interfere with biological processes in foreign organisms to impair function
  • activate or inhibit biological processes
  • either cure a problem or treat the symptom
• Drug sites of action

  • anatomical
  • physiological
  • pharmacological
• Drug Target

  the molecule to which the drug is binding to bring its therapeutic effect
• Drug Targets

  • receptors
  • transporters
  • ion channels
  • enzymes
  • intracellular signalling pathways
  • enzymes
  • receptors
  • transcription factors
• • drugs may have more than one target - e.g. tricyclic anti-depressants inhibit noradrenaline and serotonin transporters
  • Drugs may have "off-target" effects - they may interact with some unintended biological molecule. Drugs may be selective but not specific e.g. chlorphenamine inhibits histamine receptors (target) and muscarine acetylcholine receptors (off target, causes dry mouth and blurred vision)
  • Some off-target effects may be useful, some may be adverse effects
• What is a receptor in pharmacology?

  A target for developing drugs
• What are some other types of drug targets mentioned?

  Enzymes, transporters, and ion channels
• What are drugs often compliant with according to the presentation?

  Lipinski's rules for low molecular weight compounds
• What is the typical molecular weight range for drugs?

  200 to 800 daltons
• What is prophylactic treatment?

  Giving a drug to prevent disease occurrence
• How can drugs restore normal function in a patient?

  By identifying and correcting biological processes
• What is the role of drugs in treating infections?

  To interfere with foreign organisms' biological processes
• What is the difference between curing a problem and treating a symptom?

  Curing addresses the root cause, treating alleviates symptoms
• What can the term "site of action" refer to?

  Anatomical site, physiological system, or specific molecule
• What is a drug target?

  The molecule to which a drug binds
• What are some common types of drug targets?

  Receptors, transporters, enzymes, ion channels
• How do tricyclic antidepressants work?

  By inhibiting noradrenaline and serotonin transporters
• What is an off-target effect?

  When a drug affects unintended targets
• What are tricyclic antidepressants used for?

  To inhibit depression
• What is the role of the serotonin transporter?

  It pumps serotonin back into neurons
• What does the noradrenaline transporter do?

  It pumps noradrenaline back into neurons
• What is an off-target effect?

  Unintended effects caused by drug binding
• How can off-target effects be beneficial?

  They can improve the activity of the drug
• What is the intended effect of chlorphenamine?

  To inhibit histamine receptors
• What are adverse effects in drug action?

  Unwanted effects caused by off-target binding
• Where are receptors commonly found?

  In the cell membrane
• What role do receptors play in signaling?

  They bind molecules and send signals
• How can drugs alter receptor signaling?

  By activating or preventing ligand binding
• What is the beta2 adrenergic receptor used for?

  To treat asthma
• What is chirality in drug design?

  It refers to the mirror image of molecules
• Why is flexibility important in drug binding?

  It helps the drug fit into the binding pocket
• What types of bonds typically hold drugs in place in receptors?

  Ionic, hydrophobic, and hydrogen bonds
• What are ligand-gated ion channels?

  Receptors that allow ions in response to binding
• What are G-protein coupled receptors?

  Receptors that activate G-proteins upon binding
• What is a partial agonist?

  A drug that never gives maximum response
• What is the difference between an agonist and an antagonist?

  Agonists activate receptors; antagonists block them
• How do full agonists differ from partial agonists?

  Full agonists achieve maximum response; partial do not
• What is the significance of drug concentration in receptor response?

  Higher concentration can lead to maximum response
• What is the role of the effector system in signaling?

  It transmits signals after receptor activation