Gillman M A, Kok L, Lichtigfeld F J
Eur J Pharmacol. 1980 Jan 25;61(2):175-7. doi: 10.1016/0014-2999(80)90160-0.
The effect of naloxone on nitrous oxide analgesia in man has been investigated. The paradoxical response so obtained indicates the possibility of a dural system mediating the pain response in man. These results support previous animal experiments indicating that nitrous oxide analgesia is mediated by the opiate receptors.