intracellular fluid
fluid inside cells (~67% body fluid)
extracellular fluid
body fluid outside cells
1/4 plasma
3/4 interstitial fluid
sensory/afferent component
processing component
efferent/motor component
neuron
glial cells
astrocytes
microglia
oligodendrocytes
ependymal cells
unipolar neuron
multipolar neuron
intracellular Na+ concentration
15 mM
Intracellular K+ concentration
150 mM
Extracellular Na+ concentration
145 mM
Extracellular K+ concentration
5 mM
neuronal resting membrane potential (RMP)
-70 mV
excitability
equilibrium potential
K+ equilibrium potention
-90mV
Na+ equilibrium potential
+60mV
action potential
depolarization