JZL184 (neat) was dissolved by vortexing, sonicating, and gentle heating directly into 4:1 v/v PEG300:Tween80 (10, 4, 2, or 1 mg ml-1). Male C57Bl/6J mice (6-8 weeks old, 20-26 g) were intraperitoneally (i.p.) administered JZL184 or a 4:1 v/v PEG300:Tween80 vehicle without JZL184 at a volume of 4 ul g-1 weight (40, 16, 8, or 4 mg kg-1 by the dilutions above). After the indicated amount of time, mice were anesthetized with isofluorane and sacrificed by decapitation. Brains were removed, hemisected along the midsagittal plane, and each half was then flash frozen in liquid N2. One half of the brain was prepared as described above for protein analysis and the other half was used for metabolite analysis. The selective inhibition of FAAH by URB597 was achieved in a similar manner as described above, except URB597 was dissolved by sonication into 18:1:1 v/v/v saline:emulphor:ethanol (1 mg ml-1) and administered i.p. at a volume of 10 μl g-1 weight (10 mg kg-1 final dose). Oral administration was performed exactly as described for i.p. administration, except that the vehicle was PEG300.