"The NMDA receptor also has an unusual form of voltage-regulation in which
the open channel is occluded ar normal resting potential by magnesium ion in
the extracellular fluid. Depolarization drives the magnesium ion out of the
channel, allowing other ions to pass. Thus, glutamate is most effective in
opening the NMDA channel when the cell is depolarized."
The answer would appear to be magnesium, not glycine, is required. Unless I
misunderstood the question and you were talking about a specific part of the
protein sequence in the NMDA channel.
> are voltage channels (in mammals at least) ever involved in conveyance of
> impulses from one neuron to another, or are they involved only in propagation
> of action potential (and dendritic potential?)
Good question! Goes right along with William Calvin's original post about NMDA
channel's "crossing" the NT/voltage line. Hopefully Dr Calvin has the answer....
Just a EE who would _really_ like to understand just ONE of his thoughts ...
at the neural level! :-)