NMDA voltage-dependent property

Figure 10.9. Biophysical properties of the N-methyl-D-aspartic acid receptor. The current voltage (i/v) relationship measured in physiological solutions shows a region of negative slope conductance at hyperpolarized potentials. Little inward current is observed until the cell is substantially depolarized. However, when Mg + is removed from the bathing medium the i/v relationship follows Ohm s law and is represented by a straight line. The reason for this behavior is that Mg + block NMDA receptors in a voltage dependent manner (see main text).

Riluzol antagonizes glutamatergic transmission via different mechanisms indirect blockade of NMDA receptors (modification of receptor phosphorylation status), inhibition of excitatory amino acid release by an agonist effect on an unknown receptor bound to protein G or interaction with voltage-dependent sodium channels (depressor effect on neurones with a high tonic activity spontaneously). The pharmacological properties of the compound can be explained by these mechanisms anti-seizure, anti-ischaemia, antagonism of MPTP cytotoxicity [201]. 

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