Nitrous oxide inhalation does not influence plasma concentrations of beta-endorphin or Met-enkephalin-like immunoreactivity.
S F Evans, M Stringer, M D Bukht, W A Thomas, S J Tomlin
British Journal of Anaesthesia June 1985 DOI: 10.1093/bja/57.6.624 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Sample size | 10 |
| Population | Pain-free, unstressed volunteers |
| Intervention | Nitrous oxide |
| Dose | 30% nitrous oxide in oxygen |
| Key findings | Breathing 30% nitrous oxide produced plateau blood concentrations and subjective effects but no significant changes in plasma immunoreactive beta-endorphin, methionine-enkephalin, or ACTH. The authors conclude that, absent nociceptive input, nitrous oxide's effects are unrelated to peripheral concentrations of these endogenous opioid peptides. |
Abstract
The possibility that nitrous oxide releases endogenous opioid peptides into the circulation has been tested in 10 pain-free, unstressed volunteers breathing 30% nitrous oxide in oxygen. Despite achieving plateau concentrations in venous blood, accompanied by subjective effects, there were no significant changes in plasma concentrations of immunoreactive beta-endorphin, methionine-enkephalin or ACTH. These results indicate that, in the absence of nociceptive input, the effects of the inhalation of nitrous oxide are unrelated to alterations in peripheral concentrations of these endogenous opioid peptides.