Glial-neural interaction demonstrated by the injection of Na+ and Li+ into cortical glia.

Injection of Na+ or Li+ into cortical glia evokes glial depolarization, discharge of adjacent neurons, and vascular pulsation. The effects can be explained by the extrusion of K+ from glia after cation injection, glial swelling, and the slow removal of the cation from glia. The data suggest that the reduced rate of reuptake of K+ into Na+-loaded glia results in epileptiform firing of neurons, and support the hypothesis that glia function to buffer the environment of neurons.