Riluzole (PK 26124, RP-54274) is a glutamate release inhibitor with neuroprotective, anticonvulsant, anxiolytic and anesthetic qualities. In vitro
Riluzole inhibits the release of glutamic acid from cultured neurons, and from brain slices. These effects may be partly due to inactivation of voltage-dependent sodium channels on glutamatergic nerve terminals, as well as activation of a G-protein-dependent signal transduction process. Electrophysiologic experiments performed on isolated excitatory amino acid receptors expressed in the Xenopus oocyte have revealed that Riluzole inhibits currents evoked by N-methyl-D-aspartate (NMDA) (IC50 = 18 μM) and kainic acid (IC50 = 167 μM). Riluzole has been shown to stabilize inactivated sodium channels in frog sciatic nerve, in rat cerebellar granule cells, and on recombinant rat sodium channels expressed in Xenopus oocytes (Ki = 0.2 μM). Riluzole also blocks some of the postsynaptic effects of glutamic acid by noncompetitive blockade of NMDA receptors. Tiluzole protects cultured neurons from anoxic damage, from the toxic effects of glutamic-acid-uptake inhibitors, and from the toxic factor in the CSF of patients with amyotrophic lateral sclerosis.
In vivo
Riluzole can easily cross the blood-brain barrier. Riluzole has neuroprotective, anticonvulsant, and sedative properties in vivo. In a rodent model of transient global cerebral ischemia, a complete suppression of the ischemia-evoked surge in glutamic acid release has been observed by Riluzole treatment (8 mg/kg i.p.). Cell Data
