Characterization of the discriminative stimulus effects of nitrous oxide
VCU Scholars Compass January 1, 2014 Kellianne J. Richardson 1 citation
Nitrous oxide (N2O) is used as an anesthetic and is also abused, but the receptors responsible for its intoxicating effects are poorly understood. In mice trained to discriminate 60% N2O from oxygen, N2O produced concentration-dependent full substitution for itself, with full substitution requiring 7 minutes of exposure and rapid offset after cessation. The abused vapor toluene produced the most robust substitution, fully substituting for N2O in 7 of 8 subjects, suggesting shared neurochemical mechanisms. NMDA receptor open-channel blockers partially substituted, while GABAA agonists, opioids, and other drugs did not. No drug produced over 80% N2O-lever selection, indicating other neurochemical contributors remain unknown.