The Neuron AP and Synaptic Transmission Flashcards
Extracellular Ca2+ blocks what channels?
blocks fast Na+ channels.
What are 2 primary factors influencing conduction velocity in nerves?
cell diameter and myelination
the greater the diameter and more the myelination the faster the conduction velocity
What are some ion disturbances that can lead to decreased neuronal excitability/conduction?
hypokalemia
chronic hyperkalemia
hypercalcemia
What are some conditions that can lead to loss of neurons/demyelination resulting in decreased neuronal excitability/conduction?
Guillain-Barre
ALS (amyotrophic lateral sclerosis)
aging
What are some toxins/drugs that can lead to decreased neuronal excitability/conduction?
local anesthetics (“Caine” drugs)
TTX (tetrodotoxin)
STX (saxitoxin)
What are some issues/ conditions affecting NMJ that can lead to decreased neuronal excitability/conduction?
depolarizing Nm blockers
non-depolarizing Nm blockers
Lambert-Eaton
Myasthenia Gravis
Botulinum
What are some ion disturbances that lead to Increased neuronal excitability/conduction?
acute hyperkalemia
hypocalcemia
What are some conditions leading to loss of neurons/demyelination that cause increased neuronal excitability/conduction?
Multiple Sclerosis
What are some toxins/Drugs that lead to increased neuronal excitability/conduction?
CTX (ciguatoxins)
BTK
What are some issues/conditions affecting the NMJ that can lead to increased neuronal excitability/conduction?
AchE inhibitors
Latrotoxin
Words describing decreased neuronal excitability/conduction?
hyporeflexia, paralysis, sensory deficits, weakness, ataxia
What are some words describing increased neuronal excitability/conduction?
hyperreflexia, spasms muscle fasciculations, tetany, tremors, paresthesias, and convulsions.
