Brain 2-Arachidonoylglycerol Levels Are Dramatically and Rapidly Increased Under Acute Ischemia-Injury Which Is Prevented by Microwave Irradiation

Lipids. 2016 Apr;51(4):487-95. doi: 10.1007/s11745-016-4144-y. Epub 2016 Mar 28.


The involvement of brain 2-arachidonoylglycerol (2-AG) in a number of critical physiological and pathophysiological regulatory mechanisms highlights the importance for an accurate brain 2-AG determination. In the present study, we validated head-focused microwave irradiation (MW) as a method to prevent postmortem brain 2-AG alterations before analysis. We compared MW to freezing to prevent 2-AG induction and estimated exogenous and endogenous 2-AG stability upon exposure to MW. Using MW, we measured, for the first time, true 2-AG brain levels under basal conditions, 30 s after brain removal from the cranium, and upon exposure to 5 min of brain global ischemia. Our data indicate that brain 2-AG levels are instantaneously and dramatically increased approximately 60-fold upon brain removal from the cranium. With 5 min of brain global ischemia 2-AG levels are also, but less dramatically, increased 3.5-fold. Our data indicate that brain tissue fixation with MW is a required technique to measure both true basal 2-AG levels and 2-AG alterations under different experimental conditions including global ischemia, and 2-AG is stable upon exposure to MW.

Keywords: 2-Arachidonoylglycerol; Analysis; Brain; Endocannabinoids; Injury; Ischemia; Mass spectrometry; Microwave; Stroke.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Arachidonic Acids / analysis*
  • Brain / radiation effects*
  • Brain Ischemia / metabolism*
  • Endocannabinoids / analysis*
  • Glycerides / analysis*
  • Microwaves
  • Rats
  • Rats, Sprague-Dawley
  • Tissue Fixation / methods*
  • Up-Regulation / radiation effects


  • Arachidonic Acids
  • Endocannabinoids
  • Glycerides
  • glyceryl 2-arachidonate