title: A randomized placebo-controlled trial of an NMDA receptor antagonist in sleep-disordered breathing.
abstract: Hypoxemia is a powerful stimulus of glutamate release in the central nervous system (CNS) and a hallmark phenomenon in sleep disordered breathing (SDB). Glutamate effects that include neuronal damage and apoptosis following hypoxemia and apnea following microinjections in animal models are in part mediated via postjunctional N-methyl-D-aspartate (NMDA) receptors. This was a double blind, randomized, placebo-controlled single dose cross-over study of the NMDA receptor antagonist AR-R15896AR in 15 male patients with moderate to severe SDB. Seven patients received 120 mg and eight patients received 350 mg AR-R15896AR or corresponding placebo (given by 2 h infusion) starting half an hour before estimated sleep onset. AR-R15896AR concentrations were in line with the predicting kinetic model. A standard polysomnographic montage was applied. Repeated plasma samples were obtained in nine patients for analysis of plasma glutamate. Glutamate concentration in plasma did not change overnight and was unrelated to severity of SDB. Overall AHI (apnea-hypopnea index; primary efficacy variable) or investigated oxygen saturation variables were not significantly changed after AR-R15896AR at either dosage level. Side effects were mostly confined to the higher dose level and included vivid dreams, nightmares as well as in two cases mild hallucinations. The previously postulated role of glutamate in SDB could not be confirmed after AR-R15896AR induced NMDA-receptor blockade.
authors.affiliation: Sleep Laboratory, Department of Allergology and Pulmonary Medicine, Sahlgrenska University Hospital, Göteborg, Sweden. stefan.thorvaldsson@lungall.gu.se
authors.forename: Stefan
authors.initials: S
authors.lastname: Torvaldsson
authors.forename: Ludger
authors.initials: L
authors.lastname: Grote
authors.forename: Yüksel
authors.initials: Y
authors.lastname: Peker
authors.forename: Hans
authors.initials: H
authors.lastname: Basun
authors.forename: Jan
authors.initials: J
authors.lastname: Hedner
mesh_terms: D000328:Adult; D018592:Cross-Over Studies; D004305:Dose-Response Relationship, Drug; D004311:Double-Blind Method; D005260:Female; D018698:Glutamic Acid / Q000097:blood; D006801:Humans; D000860:Hypoxia / Q000097:blood / Q000188:drug therapy; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D011725:Pyridines / Q000009:adverse effects / Q000627:therapeutic use*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors*; D020181:Sleep Apnea, Obstructive / Q000097:blood / Q000188:drug therapy*
chemical_list: D011725:Pyridines; D016194:Receptors, N-Methyl-D-Aspartate; C096406:alpha-phenyl-2-pyridineethanamine dihydrochloride; D018698:Glutamic Acid