Traumatic brain injury triggers the accumulation of harmful mediators that may lead to secondary damage1,2. Protective mechanisms to attenuate damage are also set in motion2 . 2- Arachidonoyl glycerol (2-AG) is an endogenous cannabinoid, identified both in the periphery and in the brain, but its physiological roles have been only partially clarified. Here we show that, after injury to the mouse brain, 2-AG may have a neuroprotective role in which the cannabinoid system is involved. After closed head injury (CHI) in mice, the level of endogenous 2- AG was significantly elevated. We administered synthetic 2-AG to mice after CHI and found signi®cant reduction of...
