MSS - Drugs

  1. Hemicholinium
    Potent competitive inhibitor of choline reuptake --> decrease in ACh synthesis --> synaptic fatigue
  2. alpha-Latrotoxin
    Black Widow Spider Toxin: causes excessive release of ACh
  3. Botulinum Toxin A-G
    • From Clostridium botulinum; inhibits release of ACh from nerve terminal (as does tetanus toxin).
    • "Botox" is used to treat focal dystonias and spasms associated with cerebral palsy, hyperhydrosis, wrinkles, etc.
  4. Heavy Metals
    • Lead, cadmium, etc.
    • Potent antagonists of calcium entry into nerve terminal and inhibits ACh release (only a submicromolar concentration is needed to cause this)
  5. Neostigmine, sucinylcholine, physostigmine
    inhibit AChE to increase [ACh] in cleft; for glaucoma and myasthenia gravis.
  6. Curare
    • binds with high affinity to nicotinic AChR, blocking bindingn of ACh. Leads to paralysis.
    • Use curare or curare-like drugs to induce muscle relaxation during abdominal surgery.
  7. Alpha-bungarotoxin
    cobra snake venom; binds irreversibly to AChR --> paralysis
  8. Organophosphates (insecticides, nerve gases)
    Irreversible inactivation of AChE
  9. Nicotine affects what kind of muscle?
    • Skeletal - causes contraction
    • Crude extract from tobacco, containing nicotine
  10. Muscarine affects what kind of muscle?
    • Smooth - causes contraction or glandular secretion
    • Crude extract from the Amanita mushroom containing muscarine
  11. Responses to nicotine can be blocked by ______ but not ________.
    By tubocurarine, but not by atropine
  12. Responses to muscarine can be blocked by ______ but not ________.
    By atropine, but not tubocurarine.
Card Set
MSS - Drugs
MSS - Drugs