N-Methyl-d-Aspartate Receptor Channel Blocker–Like Discriminative Stimulus Effects of Nitrous Oxide Gas

Abstract

Nitrous oxide (N 2 O) gas is a widely used anesthetic adjunct in dentistry and medicine that is also commonly abused. Studies have shown that N 2 O alters the function of the N-methyl-Daspartate (NMDA), GABA A , opioid, and serotonin receptors among others. However, the receptors systems underlying the abuserelated central nervous system effects of N 2 O are unclear. The present study explores the receptor systems responsible for producing the discriminative stimulus effects of N 2 O. B6SJLF1/J male mice trained to discriminate 10 minutes of exposure to 60% N 2 O 1 40% oxygen versus 100% oxygen served as subjects. Both the high-affinity NMDA receptor channel blocker (1)

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