Ion Channels in Neurophysiology and Disorders Flashcards
brain weight and energy consumption
~1.3 kg / 2.3% of body weight
~20% of energy consumption at rest
major energy source is glucose
resting membrane potential of a neuron and skeletal muscle
neuron: -65mV
muscle: - 80mV
how is membrane voltage measured
the patch clamp method
how is the intensity of a sensation (e.g. spiciness) increased
increasing the frequency of firing action potentials
what are the biological carriers of charges in conduction of energy
K+, Na+, Ca2+, Cl-
relative concentration gradients of conductive ions
high K+ outside the cell
high Na+, Ca2+, Cl- inside the cell
difference between the roles of ion channels and ion transporters
ion channels: responsible for generating electrical signals
ion transporters: responsible for generating concentration difference of ions
where are AMPA and NMDA receptors located on a neuron
what is their role
mainly on spines
excitatory
where are GABA receptors located on a neuron
what is their role
mostly on dendritic shafts
inhibitory
what is the axon initial site
what is its role
start of the axon from the cell body
site where information integrates, if beyond threshold it fires an AP
what are pre-synaptic boutons
what is their role
site where voltage gated Ca2+ channels are activated by APs leading to exocytosis of vesicles
what was Golgi’s reticular theory of synaptic connectivity
neurites are fused to form a continuous network like the vasculature
what was Cajal’s “neuron doctrine” theory of synaptic connectivity
neurites are not continuous and communicate by contact
why use a chemical signal and not just one continuous electrically connected system
what is the synaptic assembly
scaffold proteins that hold other proteins in the active zone
