ions in brain

what could excitation predomination in the brain lead to

can lead to neurological diseases like seizures and epilespy

what could inhibition predomination in the brain lead to

coma or even death

what controls the concentration gradient across neuronal plasma membrane

Na+/K+ATPase

role of Na+/K+ ATPase

actively transports:

• Na+ from inside to outside neurone

• K+ from outside to inside neurone

what is the overall intracellular concentration of Na+ and K+ in neurone (high/low?)

• intracellular Na+ = low

• intracellular K+ = high

why is the intracellular concentration of Ca2+ also low

• because it binds to intracellular proteins

• because it is transported and stored in sarcoplasmic reticulum which form intracellular Ca2+ stores

how is chloride electrochemical gradient maintained across plasma membrane

by chloride transporters e.g. K+/Cl- cotransporters

what does K+/Cl- cotransporter do

constantly pumps Cl- OUT of the neurone whilst pumping K+ IN which generates a concentration gradient 

summary of intracellular and extracellular concentrations of Na+, K+, Ca2+, Cl-