Question

"interpret the diagram"

Answer 1

1. The glutamate causes an influx of ca2+ ions into the nerve cell akin to what occurs during depolarization. However, this occurs excessively without regulation (due to excessive stimulation by the glutamate) that  eventually causes nerve injury through cytotoxic edema.

2. When the ca2+ levels are lowered during stroke, then nerve cell injury would be obviated hence enabling the chances of restoration of nerve cell function.   This would happen because there would be no excess calcium ions to influx when the NMDA receptors are excessively stimulated by the glutamate molecules.