Administration of URB597, oleoylethanolamide or palmitoylethanolamide increases waking and dopamine in rats
Laboratory studyOther animals
- Design
- Laboratory study
- Subjects
- Male Wistar rats, implanted with EEG/EMG electrodes and brain cannulae
- Dose used in the study
- Palmitoylethanolamide, oleoylethanolamide or the FAAH inhibitor URB597, microinjected (10, 20 or 30 micrograms) into the lateral hypothalamus or dorsal raphe nucleus
- Duration
- Single-dose pharmacological trials, with EEG/EMG recording and later microdialysis sampling
- What was measured
- Time spent awake, in slow-wave sleep and in REM sleep by EEG/EMG; EEG power in the alpha, delta and theta bands; and dopamine levels in the nucleus accumbens by microdialysis and HPLC.
What the authors reported
In this laboratory study:
- All three compounds increased waking and reduced both slow-wave sleep and REM sleep when injected into either brain region during the lights-on period.
- Dopamine levels in the nucleus accumbens rose after injection of any of the three compounds.
- The authors conclude palmitoylethanolamide, like the other two compounds, promotes wakefulness in rats, an effect they link to the rise in dopamine and suggest is indirectly mediated by anandamide.
Limits of this study
Rat brain-injection study, not oral dosing and not human data. Palmitoylethanolamide here is shown to promote wakefulness, which is a different question to whether oral supplementation affects human sleep quality; the two are not directly comparable. Small group sizes typical of this kind of neurophysiology study; exact numbers per group are not given in the abstract.
Source
PubMed 21779318 · doi:10.1371/journal.pone.0020766
Entry checked against the abstract on PubMed on 2026-09-22. The dose shown is the dose the researchers used. It is not a recommendation. How to read this page.