"The focus of the study is on the plentiful neurons that communicate with each other through the neurotransmitter glutamate. While glutamate is a necessary excitatory substance in the nervous system, in excess, it overstimulates and becomes toxic - excitotoxic - to neurons. Fortunately, neighboring astrocytes can mop up the excess via molecular transporters embedded in their outer membranes. The chief transporter is a protein called EAAT2.
Earlier Rothstein's group showed that astroglia - and their EAAT2 protein -
are critical for normal neuron activity. In test rats whose astroglia lack the
EAAT2 equivalent there's not only a flood of toxic glutamate but a resulting
neuron death that leads to paralysis."