Neuro Exam 1.11

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Neuro Exam 1.11
2013-02-10 16:00:26
neuroscience neuroanatomy neurology

review of neuro lecture 11 for exam 1
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  1. Hyperkalemia:
    increased levels of K in blood
  2. What causes hyperkalemia?
    renal failure (kidneys don't filter K)
  3. What happens during hyperkalemia?
    • concentration gradient causes diffusion into interstitial space
    • changes in ratio of intracellulr to extracellular K
    • shift in RMP that decreases intracellular negativity
    • RMP closer to threshold, so easier to generate AP
    • Causes excessive contractions of smooth mm
  4. What symptoms occur during hyperkalemia?
    • cramping of GI tract
    • Cardia: very rapid HR --heart won't fill (can result in death)
  5. Hypokalemia:
    decreased level of K in blood
  6. What causes hypokalemia?
    excessive dehydration, vomiting, diarrhea, etc.
  7. What occurs during hypokalemia?
    • migration of K from interstitial to intravascular (blood) --trying to reach equilibrium
    • ratio increases causing hyperpolarization
    • RMP farther from threshold, so harder to fire
  8. What does hypokalemia cause?
    decrease in activity of muscle (bradycardia, decreased peristalsis, and constipation
  9. Lidocaine
    local anesthetic
  10. Lidocaine chemical binds to:
    voltage-gated channel on receptor organs and axons of passage
  11. What does lidocaine do?
    closes Na voltage-gated channels
  12. What does closing Na voltage-gated channels do?
    • Na can't pass through channel
    • depolarization can't occur, therefore no graded potential or AP
  13. What is lidocain used for?
    • pain
    • nerve blocks
  14. Curare:
    naturally occurring plant compound that binds to nicotinic receptor sites
  15. What is the synthetic version of curare used in anesthesia?
  16. What does curare compete with?
  17. What does curare compete with ACh for?
    receptor site
  18. Curare acts as an antagonist to:
  19. If curare is injected, it:
    competes for nicotinic receptors associated w/ MEP, and skeletal mm can't contract
  20. What does curare do to mm?
    paralyzes them
  21. What is curare used in?
  22. Succinylcholine is similar to:
  23. What is succinylcholine?
    • NMJ blocker
    • antagonist
  24. What does succinylcholine prevent?
    AP in skeletal mm
  25. Succinylcholine is an anesthetic to:
    paralyze the pt during surgery
  26. To reverse the anesthesia effects of succinylcholine, pts are given:
  27. Anticholinesterase drugs prevent:
    action of ACh-esterase
  28. What is ACh-esterase?
    enzyme that naturally breaks down ACh
  29. What are some examples of anticholinesterase drugs?
    • neostigmine
    • physostigmine
  30. Anticholinesterase drugs increase the volume of:
    ACh in NMJ
  31. What do anticholinesterase drugs do in the synaptic cleft?
    • increase AP
    • increase skeletal mm contractions
  32. Anticholinesterase drugs prolong:
    mm contractions b/c you aren't breaking down ACh
  33. When ACh isn't breaking down, what happens?
    • leads to convulsions and respiratory distress (respiratory arrest)
    • suffocation if diaphragm is involved
  34. What is Anticholinesterase drug used for?
    • antidote for chemical warfare agents
    • to treat myasthenia gravis
  35. Myasthenia gravis:
    neuromuscular disorder characterized by variable weakness of voluntary mm
  36. Myasthenia gravis improves w/:
  37. Myasthenia gravis worsens w/:
  38. What mm does myasthenia gravis cause weakness and fatigue to?
    • extrinsic eye mm (causing double vision)
    • soft palate
    • pharynx
    • mastication
    • shoulders
    • respiratory mm
  39. Myasthenia gravis causes destruction of:
    ACh receptors on postsynaptic membrane at MEP (Ach can't bind and AP can't continue)
  40. You treat myasthenia gravis w/:
    acetylecholenesterase drugs
  41. How is myasthenia gravis discovered?
    lesion on skeletal mm
  42. What type of disease is myasthenia gravis?
    progressive, autoimmune disease
  43. Botulinum toxin is produced by:
    clostridium botulinum bacteria
  44. Botulinum toxin prevents:
    release of ACh at NMJ by blocking calcium at presynaptic membrane
  45. What does botulinum toxin paralyze?
    presynaptic membrane
  46. What does botulinum toxin prevent by paralyzing the presynaptic membrane?
    release of toxin into cleft by blocking Ca ligand channels
  47. What happens if there is no release of ACh?
    no end plate potential of sarcolemma of mm and can't contract (paralyzed)
  48. What is botulinum toxin commonly known as?
    food poisoning
  49. What does no influx of Ca cause?
    • no fusion pore comples
    • no transmission of AP
    • no mm contraction (if diaphragm, can suffocate)
  50. What is a diluted form of botulinum toxin used for?
    • plastic surgery
    • botox, called a pharmacological dennervation (lasts 3-4 mo)
  51. If not treated for botulinum toxin, you die of:
  52. Nerve gases function as:
    inhibitors of AChase
  53. What do nerve gases cause?
    increase in ACh
  54. What does the increased ACh from nerve gases result in?
    • activity of effector organs:
    • lacrimal glands, salivary glands, cardiac mm, skeletal mm
  55. Nerve gases cause the lacrimal glands to:
    excessively tear
  56. Nerve gases cause the salivary glands to:
    excessively drool
  57. Nerve gases cause the cardiac mm to:
    tachycardia, leads to heart failure
  58. Nerve gases cause the skeletal mm to:
    go into seizure
  59. What is an antidote to nerve gases?
  60. What is atropine?
    an ACh antagonist
  61. What does prozac block?
    reuptake of serotonin
  62. The blocking of reuptake of serotonin from prozac involves:
    pre and post-synaptic membranes
  63. Blocking of reuptake of serotonin from prozac occurs via:
  64. Blockage of reuptake of serotonin allows:
    serotonin to remain in receptor
  65. Prozac may have a positive effect for what disorder?
    depression, but it could cause side effects elsewhere
  66. What does Aspirin come from?
    willow trees
  67. What is aspirin useful in?
    pain reduction
  68. What does aspirin break down to reduce pain?
  69. What does prostaglandin do?
    activates Na channels
  70. Aspirin doesn't transmit what kind of info?
  71. Aspirin causes neurons to not convey:
    pain to NS